Unit 1

Unit 1 Sustainable Ecosystems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .TR-1-2

Chapter 1 Nutrient Cycles and Energy Flow. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .TR-1-8
Activity 1-1 How Disturbed Is Too Disturbed? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . TR-1-8
1.1 Sustainability. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . TR-1-10
Activity 1-2 What Symbol Would You Choose?. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . TR-1-14
1.2 The Biosphere and Energy. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . TR-1-16
1.3 Extracting Energy from Biomass . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . TR-1-21
Activity 1-3 Recycling in Ontario . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . TR-1-25
Plan Your Own Investigation 1-A Fertilizers and Algae Growth . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . TR-1-28
Inquiry Investigation 1-B The Chemistry of Photosynthesis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . TR-1-30
Inquiry Investigation 1-C Soil-water Acidity and Plant Growth . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . TR-1-32
Plan Your Own Investigation 1-D Can a Plant Have Too Much Fertilizer? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . TR-1-34
Chapter 1 Review . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . TR-1-36

Chapter 2 Populations and Sustainable Ecosystems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . TR-1-38

Activity 2-1 Reducing Wildlife Mortality with Fences . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . TR-1-38
2.1 Populations and Resources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . TR-1-40
Activity 2-2 Graphing Population Change . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . TR-1-44
2.2 Interactions Among Species . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . TR-1-46
Activity 2-3 What Was for Dinner? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . TR-1-49
2.3 Human Niches and Population . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . TR-1-51
2.4 Ecosystem Services . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . TR-1-55
Activity 2-4 Ecotourism and Monarch Butterflies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . TR-1-58
Data Analysis Investigation 2-A Is the Winter Skate Endangered in Nova Scotia? . . . . . . . . . . . . . . . . . . . . . TR-1-61
Inquiry Investigation 2-B What Happens When Food is Limited? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . TR-1-63
Data Analysis Investigation2-C Putting Your Foot in Your Mouth . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . TR-1-65
Chapter 2 Review . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . TR-1-66

Chapter 3 Biodiversity. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . TR-1-68

Activity 3-1 Biodiversity in Canada . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . TR-1-68
3.1 Measuring Biodiversity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . TR-1-70
Activity 3-2 Biodiversity Index. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . TR-1-72
3.2 Communities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . TR-1-76
3.3 Threats to Biodiversity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . TR-1-80
Activity 3-3 Alien Invasions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . TR-1-83
Activity 3-4 Plants at Risk . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . TR-1-84
3.4 Restoration Ecology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . TR-1-87
Activity 3-5 The Common Good . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . TR-1-89
Real World Investigation 3-A Zebra Mussels in Lake Ontario . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . TR-1-92
Inquiry Investigation 3-B Balancing Populations and the Environment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . TR-1-94
Chapter 3 Review . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . TR-1-96

Unit 1 Projects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . TR-1-98

Unit 1 Review . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . TR-1-102

978-0-07-072367-2 Unit 1 Table of Contents • MHR TR-1-1

 Unit 1 Sustainable Ecosystems
In this unit, students will learn how sustainable ecosystems endure and support the
organisms that live within them. They will learn that human activities can alter the
• Ecosystems are dynamic and nutrient balance within an ecosystem. Students will use and define the terms “trophic
have the ability to respond to level,” “bioaccumulation,” “cellular respiration,” and “photosynthesis.”
change, within limits, while
Students will also understand that populations become limited when resources are
maintaining their ecological
balance.
limited, and that each species occupies an ecological niche defined by abiotic and biotic
components. They will investigate how humans have broadened their ecological niche
• People have the responsibility
to regulate their impact on the
and altered their ecosystems, to increase their carrying capacity. Students will use the
sustainability of ecosystems in terms predation, competition, mutualism, and parasitism.
order to preserve them for future Finally, students will explore biodiversity. Threats to biodiversity include habitat loss,
generations. introduction of alien species, overexploitation, and breaking the connectivity among
ecosystems. Students will learn about bioremediation and bioaugmentation, and how
Sustainable Ecosystems:
restoration techniques can offset damage to an ecosystem.
Overall Expectations
English language learners may benefit from a preview of the key ideas and vocabulary
• B1 assess the impact of human
activities on the sustainability of the unit. Develop a simple concept map relating all three chapter topics to the idea
of terrestrial and/or aquatic of sustainable ecosystems. Use the map to introduce and define the terms cycle, chain,
ecosystems, and evaluate the ecosystem, abiotic, biotic, sustainability, organism, population, species, biodiversity, and
effectiveness of courses of resources, and return to the map throughout the unit to introduce and reinforce Key
action intended to remedy or
Terms and to help students connect new understandings to prior knowledge. Include
mitigate negative impacts
examples and non-examples in the concept map.
• B2 investigate factors
related to human activity that Using the Unit Opener (Student textbook page 1)
affect terrestrial and aquatic
ecosystems, and explain how
• Check what students know and believe already about sustainable ecosystems using
they affect the sustainability of BLM 1-1 Unit 1 Anticipation Guide. Then, when you have completed the unit, check
these ecosystems again and have students reflect on how and why their understandings and attitudes
• B3 demonstrate an may have changed.
understanding of the dynamic • ELL The forest ecosystem is very familiar to Canadian students but may be unfamiliar
nature of ecosystems,
particularly in terms of ecological
to English language learners. Discuss the names and characteristics of common forest
balance and the impact of human animals and plants. This activity could be done in partners or small groups.
activity on the sustainability • DI Ask spatial learners to draw some of the animal warning road signs they have
of terrestrial and aquatic
seen either in the local area or in their travels. For example, students may have seen a
ecosystems
duck-crossing or turtle-crossing sign if they were near a marsh. Students can use chart
Materials paper, mini whiteboards, or the front board to sketch their signs.
Please see page TR-35 for a list of • DI For the benefit of linguistic and interpersonal learners, arrange students into
the materials required for this unit
and other units.
groups of five or six. Have each group construct a placemat spider map (see page 566
of the student textbook), then brainstorm other ways of protecting animals from being
hit by cars on highways. Appoint one person in each group to ensure that everyone
has a chance to participate.

TR-1-2 MHR • Unit 1 Sustainable Ecosystems 978-0-07-072367-2

 Assessment OF Learning for Unit 1

Activity Evidence of Learning Supporting Learners

Unit 1 Inquiry Student selects appropriate biotic and abiotic Review abiotic and biotic components using a sample
Project components for an aquatic ecosystem. ecosystem. Have students summarize information in a
graphic organizer, for example, a Venn diagram.

Inquiry design is effective, including a Read Science Skills Toolkit 2, Scientific Inquiry, on page 532
hypothesis, dependent and independent of the textbook with students.
variables, a control, and a data collection Consider providing BLM G-5 Scientific Inquiry Organizer,
plan. and/or BLM A-3 Designing an Experiment Checklist.
Assign a peer editor to assist with planning a thorough
inquiry.

Student describes observed effects of the Consider providing BLM G-4 Making Observations and
chosen substance on the ecosystem. Inferences, and BLM A-1 Making Observations and
Inferences Checklist.

Results of the inquiry are communicated Consider providing BLM G-6 Recording an Investigation.
clearly, using text and visuals. Refer students who have gathered numerical data to Math
Skills Toolkit 3, Organizing and Communicating Scientific
Results with Graphs, on page 557 of the student textbook.

Unit 1 An Issue to Students identify three factors that threaten Using the Oak Ridges Moraine as an example, ask students
Analyze Project a specific ecosystem, and write questions to to choose one human factor impacting this ecosystem and
learn more about these factors. describe its effects. Support this discussion with illustrations
that show the connectedness of organisms, including
humans, within this ecosystem.
Have students list things they know about their ecosystem,
then review the potential threats listed in Section 3.3 to
decide which ones likely apply to their ecosystem.

Students gather and organize data to help Refer students to Math Skills Toolkit 3, Organizing and
answer their questions. Communicating Scientific Results with Graphs, on page 557
of the student textbook.
Consider providing BLM G-12 Scientific Research Planner.

Students explain multiple perspectives Consider providing BLM G-17 Worksheet for Investigating
related to issues affecting the ecosystem’s Issues.
health. Encourage students to work in pairs to suggest alternative
viewpoints to one another.

Students propose and clearly explain Consider providing BLM G-18 Decision-Making Organizer,
practical, reasonable strategies to reduce and/or BLM A-5 Investigating an Issue Checklist.
the threat.

Get Ready (Student textbook pages 2 and 3)

Prerequisite Learning
Students would benefit from understanding
• the relationships among plants and animals in habitats and communities and be able
to explain the cause-and-effect relationships that take place and affect the ecosystem.
(questions 4, 5)
• how human activities affect habitats and communities. (question 5)
• how a food chain works. (question 3)
• that ecosystems are made of interacting biotic and abiotic components. (question 1)
• the roles of producers, consumers, herbivores, carnivores, and omnivores. (question 2)
• how matter is cycled. (question 4)

978-0-07-072367-2 Unit 1 Sustainable Ecosystems • MHR 3

 Prerequisite Skills
Students need to be able to
• communicate in writing, verbally, and using a variety of media with different
audiences for a variety of purposes. (questions 6, 7, 9, and 11)
• interpret a variety of literary, graphic, and informational text. (questions 1, 9, and 10)
• proofread and edit work to correct errors and refine their expression. (questions 8
and 11)
• predict the meaning of unfamiliar words using a variety of cues. (questions 4 and 7)
• record and organize data using standard measurements in tables, graphs, or charts.
(question 10)
• make predictions based on prior knowledge, and identify patterns in data. (questions
7 and 9)
• represent the steps and results of an experimental procedure. (questions 8, 9, and 10)
• state a conclusion based on information gathered. (question 7)
Students can review some of these skills using BLM 1-2 Skills for Unit 1.
Answers
1. Biotic: bird, mammals, trees, berries, flowers, nuts and seeds, grasses
Abiotic: rocks, air, water
2. b. A vulture is a scavenger because it eats animals that it finds dead.
c. A tree is a producer because it uses energy from the Sun to create food for other
organisms.
d. A chipmunk is a consumer because it gets energy by eating other organisms.
e. A deer is a herbivore because it eats only plants.
f. A wolf is a carnivore because it eats only animals.
g. A bear is an omnivore because it eats both plants and animals.
3. Students’ food chains should show at least 3 organisms, including a consumer that
eats a consumer that eats a producer.
4. Students’ explanations should include the benefits that trees provide to different
parts of the ecosystem.
5. Students’ flowcharts should clearly show cause and effect.
6. Most collisions occur in spring and fall. This may be because animals are hungry
at those times, so approaching roadways, or because they are expanding or moving
their territories.
7. Every strategy could be effective. Students should provide a logical rational for the
one they choose.
8. Students’ strategies should include formulating a hypothesis; collecting data in
an organized, unbiased way; and displaying and analyzing the data to formulate a
conclusion.
9. Ottawa, Simcoe County, Kenora, Lanark County, Thunder Bay.
10. A bar graph or a pie chart would be appropriate. Students’ graphs should be accurate
and clearly labelled.
11. The message should state the dangers clearly, recommend strategies to avoid them,
and communicate using simple, clear language.

TR-1-4 MHR • Unit 1 Sustainable Ecosystems 978-0-07-072367-2

 Assessment FOR Learning

Tool Evidence of Learning Supporting Learners

Get Ready Students catergorize and organize Have students create a concept map based on the image on page 2
Concept Check components of an ecosystem and of the student textbook. Students should label part of the image as
their relationships. biotic or abiotic. Students should link and label the images further using
the statements from question 2 and the terms from question 4. For
question 3, English language learners could draw a food chain from an
ecosystem that is more familiar to them.

Get Ready Students read the given passage Have students deconstruct sample procedures from the textbook by
Inquiry Check and extract information to analyze looking at the number of steps, particularly how data collection is
and predict outcomes. Students described for each procedure. As a class, model a template for writing
write a step-by-step procedure a procedure and then have students write and peer-edit their own
that includes data collection. procedures for the inquiry check. English language learners could write
and edit with a partner.

Get Ready Students are able to rank the data To rank and graph the data, students can use spreadsheet software.
Numeracy and accordingly, select an appropriate Have students work in small groups to list features of effective graphs.
Literacy Check graph, and write at least Together, summarize this information using a concept attainment
300 words in the appropriate tone strategy in which students classify graphs as well designed or not.
for the mayor.
Check local radio station websites for news announcements. Provide
students with examples of these announcements as samples of a
suitable style. Have students work in groups of four to six. Ask them
to brainstorm a list of features that make each announcement effective.
Post their lists around the classroom, and conduct a gallery walk, in
which students look at the ideas of the other groups. Create a class list
of effective features of an announcement together and have students
use this to guide their writing.

978-0-07-072367-2 Unit 1 Sustainable Ecosystems • MHR TR-1-5

 Using Making a Difference (Student textbook pages 11, 77, 101)
Throughout the unit, students will encounter examples of situations where humans’ choices
affect the health and sustainability of a species or an ecosystem. There are simple choices
we can make as consumers, which drastically affect the habitats of other species (for
example, choosing a specific type of coffee or using cellphones).
Just as Yvonne Su, Allyson Parker, and Severn Cullis-Suzuki were able to make a
difference, so can students from any high school. Students can be encouraged to create
an action plan for their class or school with the intention of reducing their impact on a
specific species or ecosystem. Plans might include improving the songbird habitat on the
school grounds, or helping their parents choose shade-grown coffee or even learning to
make coffee in the morning so Mom and Dad do not have to go to the drive-through.
Their action plans could be part of the school’s EcoSchool initiative. Encourage students
to realize that even small changes can make a big difference.

Using Science at Work (Student textbook page 124)

The significance of songbird decline was so important to Dr. Stutchbury that she
incorporated it into her career as an author and a university professor. Reasons
for songbird decline include deforestation in South and Central America and the
fragmentation of forested areas in the United States. As the North American human
population spreads to rural areas, the predators and competitors (for example, jays,
crows, feral cats, foxes, and raccoons) that favour suburban habitats increase.
Songbirds are an important indicator of environmental health, biodiversity, and
sustainability. With our growing population, we still require timber for the construction
of new houses, and very little wood in North America is harvested from plantations.
The origins of most medications (approximately 80 percent) commonly prescribed in
North America are natural compounds.
To introduce this feature, consider playing a recording of local songbirds in the
classroom and displaying photographs of the birds.
An extension to the career study is suggested in question 4 on page 125. Ask students
to put themselves in the shoes of a person working in a career that they are interested
in pursuing. Direct students to include in their answer what this person (for example a
forester, an urban planner) could do to increase and protect songbird habitat.

Introducing the Unit 1 Projects (Student textbook pages 126 and 127)
Discuss with students one of the reasons scientists study ecosystems—to learn how to
protect them. Explain that the Unit 1 Projects will give students the chance to apply what
they learn to investigate some threats that humans pose to ecosystems and how we can
protect the ecosystems. Preview the Unit Projects with students. Then, looking at the
chapter titles in Unit 1, ask students to predict some things they may learn about that would
help them complete one of the projects. As students work in Unit 1, draw their attention to
concepts that may be helpful in completing one of the projects. For example, understanding
the phosphorus cycle, on page 18, can help students complete the Inquiry Project. The
investigations at the end of each chapter have been designed to help students develop both
understandings and skills that will be useful to them as they complete the Unit Projects.
Students can begin to plan their work on a Unit Project at any time after they begin the unit.
Most English language learners will find the Inquiry Project “Pollutants and Aquatic
Ecosystems” less linguistically demanding than “Protecting Ecosystems.” Hold mini-
conferences throughout the unit, to ensure understanding and to establish a time line
for completion of each task of the Inquiry Project. Peer support groups (homework clubs
with older students) could also be used in this context. If possible, invite older students
with the same first language to help your students.

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Using the Case Studies
The suggestions below provide opportunities for students of multiple learning styles to
engage in and explore issues. The strategies chosen support bodily-kinesthetic, spatial,
and interpersonal learning styles. The strategies also serve as pre-reading strategies and
scaffolds for English language learners.
Chapter 1 (Student textbook pages 8 and 9)
• Ask students to examine the graphic on page 9 and explain how the eels change in
appearance. Ask, “What part of the eels’ life cycle takes place in the great lakes?”
Record the answers on the chalkboard.
• Before reading “The Disappearing Eel” case study, provide students with an
opportunity to explore their views through a brief Four Corners activity. Post each of
the following perspectives in one corner of the classroom, read them aloud, and invite
students to move to the corner that best reflects their own view. The perspectives are
the following:
1. All species deserve equal protection.
2. Eels are a special fish species of the Great Lakes and deserve more attention than
other species.
3. Eels are water snakes that are not that important in the Great Lakes.
4. We should not intervene to protect any species.
The perspectives are printed ready for posting on BLM 1-3 Four Corners Activity.
Have students read the case ctudy, answer the questions, and then reflect on how
their views on this issue have changed. You could repeat the Four Corners activity
and allow students who changed their minds to explain why they chose a different
corner this time.
• Provide students with BLM 1-4 Eel Life Cycle, for them to record information about
the eel while they read.
Chapter 2 (Student textbook pages 72 and 73)
• Before reading the “Why Are Honeybees Disappearing?” case study, have students
stand in a value line. One end of the line could be those students who would say,
“I believe that we are doing enough to protect the bees,” and the other end could be
those students who would say, “I believe that we could do much more to protect the
bees.” Split the line in half and shift one side down so that there are now two lines of
students, facing each other. The students in each facing pair must convince each other
of their opinion, for one minute each.
• After reading the case study, either in pairs or groups of four, have students discuss any
questions their group members have, then create a concept map with 10 connections
for the disappearing honeybee, using BLM 2-2 The Disappearing Honeybee.
Chapter 3 (Student textbook pages 106 and 107)
• Brainstorm with students a brief list of plants and animals that must survive harsh
conditions over the winter. Discuss the various strategies that these species use to
survive (bears hibernate, frogs tunnel into mud, humans have developed central
heating, and some seeds require a freezing period to germinate).
• Have students work in groups to brainstorm a list of other species that have a life
cycle that completes itself in two distinctly different ecosystems.
• Remind students of the survival strategies that were discussed prior to reading the
case study. Ask students to explain the survival strategy that Dolly Varden use.
• Use a Venn diagram to help students understand the similarities and differences
between traditional knowledge and scientific knowledge. Use BLM 3-2 Traditional
Knowledge/Scientific Knowledge.

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 Chapter 1 Nutrient Cycles and Energy Flow

Materials In this chapter, students will learn that all life depends on recycled matter and that all
Please see the teaching notes matter is interconnected within an ecosystem. Students will also learn how human
for each activity for a list of the interaction can interfere with the sustainability of an ecosystem.
materials required. Please see
page TR-35 for a summary of the Using the Chapter Opener (Student textbook pages 4 and 5)
materials required in this chapter
and other chapters.
• At the chalkboard, brainstorm with students to create a word family web starting
with the word sustain. (Once you have modelled this process, students will be able
Advance Preparation to develop similar webs for other concepts on their own or in small groups.) Words
• Order or purchase plant that might be used in the web include sustenance, sustainable, sustained, sustainedly,
material, soil, and fertilizer for sustainer, and sustainability. Ensure that all students understand the meanings of
Investigations 1-A, 1-B, 1-C,
each word on the web. Sustain has a dual meaning—to provide nourishment and to
and 1-D ahead of time.
maintain. Within the context of this unit, both meanings are applicable.
• Supplies needed include Elodea,
radish, and pea seeds; fertilizer; • Work with students to compare and contrast the importance of a provincial park
soil; and foam cups. versus a World Heritage Site. Some of the objectives of a World Heritage Site include
• Inquiry Investigation 1-C, on protecting the cultural and natural importance of an area to all humanity, and
pages 40 and 41, and Plan Your protecting an area that contains habitat for threatened species. Some of the objectives
Own Investigation 1-D, on page for provincial parks include protecting representative ecosystems, and providing
42, will take several weeks to
opportunities for ecologically sustainable recreation.
complete, so have students start
• As an alternative, tell students about two Canadian parks, and then ask students to
them early in the unit, no later
than the second week. compare them:
• Students can review the Key Algonquin Park was established in 1893 as a wildlife sanctuary and to protect
Terms in Chapter 1 using the headwaters of rivers that were important for logging; it is one of Canada’s oldest
BLM 1-5 Chapter 1 Key Terms. provincial parks. Since its creation, the park has been selectively logged, yet it still
maintains a variety of wildlife including deer, wolves, and the largest population of
moose in central Ontario. Algonquin Park is classified as a Natural Environment
Park. The objectives of this type of park include protecting outstanding recreational
landscapes, and providing high-quality educational experiences.
Even though the park supports moose, deer, wolves, and canoeists, it can be argued
that the ongoing logging has frozen the ecosystem of the park in time, maintaining these
optimal conditions without ever changing or evolving.
Woodland Caribou Park, on the other hand, is classified as a wilderness park.
Wilderness parks are remote, and only accessible by boat or float plane. This type of park
allows nature to exist freely and only promotes low impact recreation.
Ask students which of these two parks best fits the definition of sustainability.

Activity 1–1 How Disturbed Is Too Disturbed? (Student textbook page 5)

Pedagogical Purpose
This activity illustrates that a system can usually tolerate some disturbance, but after a
certain point, the disturbance can cause the whole system to collapse.

Planning

Materials 24 smooth rectangular building blocks, labelled with environmental disturbances:

Deforestation Global climate change Overfishing
Disease, extinction Habitat fragmentation PCBs, DDT, excess nutrients in run-off
Draining wetlands Hurricane, tsunami, flood, ice storm Pollution (air, water, light)
Drought, desertification Meteor strike Volcanic eruption
Exotic species Nuclear bomb Wildfire

Time 5 min to label the blocks

15 min to do the activity

TR-1-8 MHR • Unit 1 Sustainable Ecosystems 978-0-07-072367-2

Background
Some environmental disturbances are natural, and others are caused by humans. In this
activity, students treat all environmental disturbances equally. In many cases, natural
disturbances such as fire are part of the ecosystem necessary to promote regeneration.
However, forest fires can also threaten homes and communities. Students may want
to develop their own opinions about whether humans should interfere with natural
disturbances like forest fires.
Activity Notes and Troubleshooting
• It is important that students take turns, and remove the blocks smoothly and slowly.
• Inexpensive versions of this game can be found at some dollar stores.
Additional Support
• DI For linguistic learners, as well as English language learners, this game can be
modified by showing different words on some of the blocks. For example,
• Show several biotic and abiotic components of an ecosystem on the blocks.
Use different colours for biotic and abiotic components.
• List Key Terms on the blocks. In order to remove a block, students must define the
word. Create a list of definitions of Key Terms for students to refer to.
• ELL After the activity, print and discuss the words balance and interdependence.
Challenge students to draw a sketch to illustrate the meaning of these words. Share
these sketches with a partner. Add these words to the concept map started at the
onset of the unit.

Study Toolkit

Strategy Page Reference Additional Support

Previewing Text Students can skim or scan the headings and Refer students to the Study Toolkit Appendix, in particular
Features subheadings throughout Chapter 1, in order to Study Toolkit 1, Preparing for Reading: Previewing Text
predict what each section will be about prior to Features, on page 563 of the student textbook.
reading.

Comparing and After reading pages 28 and 29, students can BLM G-39 Venn Diagram
Contrasting use a Venn diagram to compare and contrast Have students write sentences using these comparing words:
photosynthesis and cellular respiration. X and Y are alike because...
X and Y are not alike because...

Word Families Students can draw a word family web to record Think Literacy: Cross Curricular Approaches, Grade 9 Science
the meanings of the Key Terms lithosphere, available at STAO.ca, includes strategies to help students
biosphere, atmosphere, and hydrosphere on make connections among words.
page 13. Refer students to Study Toolkit 3, Word Study: Common Base
Words, Prefixes, and Suffixes in Science, on page 565
of the student textbook.
Work with English language learners to identify prefixes and
suffixes that can help them understand important words
throughout the chapter.

978-0-07-072367-2 Chapter 1 Nutrient Cycles and Energy Flow • MHR TR-1-9

 Section 1.1 Sustainability (Student textbook pages 7 to 20)

Sustainable Ecosystems: In this section, students will learn about the impact of human activities on sustainable
Specific Expectations ecosystems. Students will be able to explain what makes an ecosystem sustainable. They
• B1.2 evaluate the effectiveness will compare and contrast the characteristics of an unsustainable ecosystem. Students
of government initiatives in will be able to describe the relationship between Earth’s four spheres and how cycling of
Canada, and/or the efforts
water, carbon, nitrogen, and phosphorus links Earth’s spheres.
of societal groups or non-
governmental organizations,
with respect to an environmental
Common Misconceptions
issue that affects the • Some students may believe that biotic components of an ecosystem are important
sustainability of terrestrial or to sustain life, but may not appreciate the importance of the abiotic components.
aquatic ecosystems You could talk with them about what they need to survive (for example, food, water,
• B2.2 interpret qualitative oxygen) and point out that many of these requirements are abiotic.
and quantitative data from
undisturbed and disturbed
• Students may be somewhat familiar with the water cycle, but may believe that
ecosystems, communicate other components are static; that is, they do not move around in our environment.
the results graphically, and, Point out, for example, that carbon naturally cycles into and out of the atmosphere. Its
extrapolating from the data, movement is not caused by humans, but our actions affect the rate at which it moves,
explain the importance of and thus upset the balance.
biodiversity for all sustainable
ecosystems • We can counterbalance our carbon emissions by carbon sequestering and with
carbon taxes and carbon offsets. Encourage students to investigate the details of the
• B2.4 plan and conduct an
investigation, involving both different types of carbon offsets that are available, for example, where the project
inquiry and research, into how will be located, and how students can be assured that any projects they invest in will
a human activity affects water remain in place for a sufficient time period. For example, seedlings purchased as
quality, and, extrapolating part of a carbon offset program may be destroyed in five years for a new shopping
from the data and information
mall. Point out that instead of paying a “tax” for our indulgences, it may be more
gathered, explain the impact of
this activity on the sustainability effective to make and demand better choices.
of aquatic ecosystems
Background Knowledge
• B3.1 compare and contrast biotic
and abiotic characteristics of Easter Island was populated from the west by Polynesians. While the human population
sustainable and unsustainable probably contributed to most of the deforestation, due to the island’s fairly southerly
terrestrial and aquatic latitude, it may also have been influenced by a climate change event called the Little Ice
ecosystems Age. It is often assumed that the population’s drastic decline on Easter Island was due to
• B3.4 identify the earth’s four starvation; however, the islanders were also the target of Peruvian slavers in the 1860s.
spheres, and describe the The west coast has a great variety of hummingbirds; in Ontario, we usually only see
relationship that must exist
the ruby-throated hummingbird. Only the male has the distinct red throat; the female is
between these spheres if
diversity and sustainability iridescent green with a white throat. Occasionally a rufous hummingbird will stray east of
are to be maintained the Rockies and may be seen in the fall. The male has an orange/red head and the female
looks similar to the female ruby-throated hummingbird but with orange/red flanks. If you
want to attract hummingbirds to your schoolyard, you need to put out a feeder in mid- to
late April when they are returning. Be sure to have a lot of red flowers around.
Although many fungi have a symbiotic relationship with plants, not all fungi are
beneficial to trees and plants. Beneficial fungi such as Basidiomycota, Ascomycota, and
Zygamycota produce what are called mycorrhiza—fine hair-like strands that bond to
the roots of plants, assisting them with water and nutrient uptake. Other fungi such
as Armillaria are pathogens and cause root rot, among other symptoms. Armillaria
can often be identified by mushrooms growing at the base of trees, usually with red or
honey-coloured caps.
If you are going to a rock concert or another event, you may be asked to purchase
carbon offsets to help counterbalance the band’s carbon emissions from putting on an
elaborate show and travelling around on tour. Carbon offsets may include investing in
renewable energy production such as wind farms, or they may also include investing in
forestry projects. Before spending money purchasing carbon offsets, it is wise to consider
what they will be used for.

TR-1-10 MHR • Unit 1 Sustainable Ecosystems 978-0-07-072367-2

 Living things depend on biotic and abiotic resources. A population will grow
only as fast as its most limiting resource will allow. For example, algae in a pond may
have access to a lot of water and sunlight, but limited access to phosphorus will slow
down their growth. If phosphorus is dumped into the pond, the algae will grow until
another resource limits their growth. Often this rapid growth upsets the balance of
the ecosystem. An analogy for limited nutrients is a class barbecue. Imagine that
you are going to host a barbecue for the entire class, and you are planning to serve
cheeseburgers. There are 30 students in your class. You brought 31 frozen burgers,
25 burger buns, and 12 slices of cheese. Although there are more burgers than students,
you can only serve 12 cheeseburgers because there are only 12 slices of cheese. The
cheese is the limiting nutrient. Analogies of this sort are very beneficial to English
language learners.

Literacy Support
Using the Text
• ELL The geography of North America may be very new to many English language
learners. A large wall map of the world and of North America are essential teaching
aids. Use these maps prior to reading this section to set the physical context for
English language learners.
Before Reading
• Have students preview the text features, looking for headings and highlighted words.
In pairs, have them predict what the main ideas of the section will be.
• ELL To help English language learners use the text features to navigate the textbook,
have a scavenger hunt. Ask students to find a feature that
• helps to understand the meaning of a word (boxes in the margin).
• explains a diagram (a caption).
• tells a big idea (a head or subhead).
• summarizes important information (the section summary).
During Reading
• Have students create a personal glossary by making a three-column table, and listing
new terms as they encounter them in the textbook, in the left column of their table.
Students can write the definition for each term in the next column, and draw a diagram
to represent the term in the third column. Tell them to pay attention to the Key Terms
in sidebars and highlighted in the textbook, and to identify base words that will help
them find the meanings of other words (for example, the base word bio means life,
and can help define biology, biosphere, and so on). Students can continue to build this
glossary as they work through the rest of the unit, and the rest of the course.
• ELLInstead of a glossary in chart form, English language learners can make flash
cards with a picture on one side of the card and a definition on the other side. They
can then use these cards to review new vocabulary.
• ELL To help English language learners relate to the concept of migration, discuss
what migration has meant to them. Talk about how many families move to new
locations for a variety of reasons. Listing the advantages that exist in Canada helps all
students understand that humans migrate as well as animals often for similar reasons.
After Reading
• To consolidate their learning, have students create a word web or another graphic
organizer to show the relationship between two key concepts they learned about in
the section. They can use this graphic organizer as a starting point for the graphic
organizer they develop in the Chapter Review.

978-0-07-072367-2 Chapter 1 Nutrient Cycles and Energy Flow • MHR TR-1-11

 Using the Images
• Before reading the passage on page 7, have students describe the image in Figure 1.1,
on page 7. You can prompt them with questions such as, “How large are the statues?”
“What does the vegetation look like?” “How could the statues have been put in place?”
Describing the image will help to engage spatial learners.
• Connect to students’ personal experience. For Figure 1.2, on page 8, ask students to
imagine they are holding a hummingbird in their hand and to describe how large the
hummingbird is in comparison to their hand.
• DI Table 1.2, Abiotic Characteristics of an Ecosystem, on page 12, shows an
example of how students can set up their own glossaries, which spatial learners may
find helpful.
• Have students complete BLM 1-9 The Nitrogen Cycle, to summarize the content of
Figure 1.6, on page 16. Then have students create their own diagram of the carbon
cycle based on page 15 of the textbook.
• ELL Use BLM 1-10 The Phosphorus Cycle, based on Figure 1.8, on page 18, to help
students predict and explain what will happen in each stage based on what they
already know. On BLM 1-10, students can record what they think is happening in the
first column for each number in the phosphorus cycle diagram. They can then use the
Think, Pair, Share strategy to refine their prediction and record that refined version in
the next column, and in the third column verify what is actually happening, using
the textbook.

Assessment FOR Learning

Evidence of Student
Tool Understanding Supporting Learners

Learning Check Students To help students identify the cause-and-effect relationships involved
questions, pages 9, • explain how the elements of an in eutrophication, have them complete BLM 1-11 Cause and Effect.
19 ecosystem interact
• describe the process of
eutrophication.

Section 1.1 Review Students describe the role Play a game

questions, page 20 nutrient cycles play in a balanced Divide the class into teams with members of diverse strengths and
ecosystem, and what can abilities. Each team must submit five questions similar to those in the
cause ecosystems to become review, with answers. Teams take turns choosing questions from other
unbalanced. groups and answering them. Students can use notes for the Section
Review to help them. Set a time limit for students to come up with an
answer. Allow opportunities to “phone a friend.”

Activity 1-2, What Symbol meets the criteria listed, Students may feel uncomfortable with their own artistic skills. Show
Symbol Would You clearly represents one or more them exemplars of varying artistic ability that all meet the criteria for
Choose?, page 11 of today’s issues, and increases the assignment and that would achieve the same level (3+ or 4).
Create a Poster awareness for the future. Allow students to use alternative media, such as computer drawing
applications, or use mini whiteboards. The lack of permanence of mini
whiteboards makes them less intimidating for students.

TR-1-12 MHR • Unit 1 Sustainable Ecosystems 978-0-07-072367-2

Instructional Strategies
• The Mystery of Easter Island is an engaging introduction to the idea of sustainability.
After students have read about Easter Island, do a concept attainment activity for
sustainability (see BLM 1-6 What Is Sustainable?). Give students a sample data set
with examples of activities that do promote sustainable environments and activities
that do not promote sustainable environments. Then give students several “testers,”
or examples, which they will have to decide for themselves where to place. A class
discussion after this activity can help reveal that the answers are not always clear, but
that there are several common factors to be considered in making each decision.
• Compare and contrast the biotic and abiotic components of the Canadian and
Mexican ecosystems required to sustain the ruby-throated hummingbird population.
This comparison can be done individually, in groups on whiteboards or chart paper, or
as a discussion at the board.
• Have students do a jigsaw brainstorming activity before reading the Abiotic
Characteristics of an Ecosystem section. Arrange students into five home groups.
Within each group, have students choose a colour—blue, red, white, green, or
black. Then have students gather into new groups of the same colour (all the greens
together, for example). Assign each colour one characteristic (for example, white
= light, red = oxygen, and so on). Have each new group brainstorm why their
characteristic is important and its effects on sustainability. Each individual should
record the information on a card. Then have students return to their home groups
and combine the information from all the cards on a larger piece of paper to create a
table summarizing all of the characteristics of an ecosystem. When this task is done,
do some round-robin sharing, and then compare the groups’ results to Table 1.2,
Abiotic Characteristics of an Ecosystem, on page 12 of the student textbook.
• DI Spatial learners could create a graphic organizer to take notes if desired.
• ELL If necessary, appoint a student in each group to scribe for English language
learners so that they will have accurate notes to take back to their home group.
• DI Bodily-kinesthetic learners might enjoy acting out the different nutrient cycles.
Divide the class into groups and assign each group one of the nutrient cycles. Each skit
should emphasize at least five stages in the cycle and should address the human impact
on the cycle. Students could choose to present in the form of a talk show, a series of
tableaus, or a “wildlife” documentary (for example, The Carbon Hunter).
• As an alternative activity, students could create a passport. Give students a blank
template for one of the cycles (BLM 1-7 The Water Cycle; BLM 1-8 The Carbon
Cycle; and BLM 1-9 The Nitrogen Cycle). Create stations around the classroom where
students can collect stamps or stickers to complete their passports. At each station,
include directions to the station where students can find the next sticker or stamp.
Different tour groups (Carbons, Nitrogens, or Phosphoruses) will follow slightly
different routes in the classroom (or around the school).

978-0-07-072367-2 Chapter 1 Nutrient Cycles and Energy Flow • MHR TR-1-13

 Activity 1–2 What Symbol Would You Choose? (Student textbook page 11)
Pedagogical Purpose
One of the big ideas of this unit is that people are responsible for regulating their impact on
the sustainability of ecosystems. The first step in this process is to increase public awareness.
One simple and effective way to do this is to create a symbol to spark public interest. In this
activity, students activate the understandings of environmental issues and human effects on
the environment that they will build on in this unit to design such a symbol.

Planning

Materials 1 sheet construction paper Tape or glue

Coloured markers Internet access
Scissors Computer lab

Time 20 min in class: 10 min to create a symbol and 10 min to discuss

Background
Successful symbols are simple and easily understood, with a clear connection to the idea
for which they stand, for example, the World Wildlife Fund’s panda. Students may all
choose to represent a different environmental issue, and so may produce different symbols.
Activity Notes and Troubleshooting
• Give students a time limit, if the assignment is an opener for discussion. “You have
10 min; it does not have to be a masterpiece.”
• Make sure the criteria for the symbols are clear:
• one symbol for current environmental problems
• one symbol for a future of increased environmental awareness
• no words are to be used
• Assign some time (for example, a 10-min period or some time at the beginning of
class the following day) for sharing ideas.
• Discuss how the questions are to be answered, in notebooks for homework or as a
discussion.
• Instead of paper, use small letter-sized whiteboards (the kind students stick in their
lockers), which are available at dollar stores. Whiteboards suggest less permanence,
reduce stress, and evoke greater participation.
• Some students may be more comfortable using a computer drawing application
instead of drawing by hand.
Additional Support
• DI This is predominantly a spatial activity. To incorporate interpersonal and
bodily-kinesthetic learning styles, encourage sharing and discussing of the results.
• ELL English language learners may prefer to use the Internet to refer to familiar
symbols from their own culture for inspiration and clarification. They may also
need more examples of what a symbol is versus a logo. Encourage all students to not
include words in their symbol, and to try to make their symbol universally meaningful
to all cultures.
Answers
1. Students’ designs may differ in colour or size, and may be biotic factors or abiotic
factors.
2. Students’ symbols might show a very one-sided relationship, such as a balance scale
with one side much heavier than the other.

TR-1-14 MHR • Unit 1 Sustainable Ecosystems 978-0-07-072367-2

Learning Check Answers (Student textbook page 9)
1. They used trees to make wooden frames to move and erect the statues, and to burn
wood. They also cleared forests for agriculture.
2. Sustain means to endure and to support.
3. Ruby-throated hummingbirds live part of the year in a tropical rain forest, and then
they stop in many ecosystems along the way as they migrate north in the spring.
They spend the summer in meadows and wetlands in Canada.
4. Biotic parts could include people, pets, houseplants, crops, grass, insects,
and bacteria.

Learning Check Answers (Student textbook page 19)

5. Eutrophication is a process in which nutrient levels in aquatic ecosystems increase,
leading to an increase in the populations of primary producers.
6. Phosphorus was found to be the main cause of eutrophication.
7. fertilizer in run-off
8. In order to get the lawn looking healthy, you probably added fertilizer. The fertilizer
improved the lawn, but it also leached into the pond, causing eutrophication and an
algae bloom that depleted the oxygen and therefore killed the fish.

Section 1.1 Review Answers (Student textbook page 20)

Please also see BLM 1-12 Section 1.1 Review (Alternative Format).
1. a healthy environment that endures and supports a variety of organisms
2. Once the forest ecosystem on Easter Island was gone, all of the resources and
processes associated with trees, such as lumber for building or fuel, and protection
from erosion, also disappeared.
3. Students can describe any three of the following: water, light, oxygen, nutrients, and
soil. Accept any reasonable response regarding the effect that human activity could
have on the abiotic part.
4. Students’ drawings should be similar to Figure 1.6, on page 16. Bacteria convert
nitrogen from the atmosphere into forms that other living things can use.
5. a. Humans can add excess phosphorus to aquatic ecosystems through fertilizer in
run-off. Phosphorus is naturally a limiting nutrient. When excess phosphorus
reaches an aquatic ecosystem, the ecosystem becomes eutrophic.
b. Farmers could participate in the Environmental Farm Plan to help reduce
fertilizer in run-off.
6. Answers will vary. Generally, scientific research in the areas of environmental toxins
and nutrient pollution causing eutrophication led to changes in laws designed to
counter the problems that science revealed.
7. Answers will vary. Sample answer: Farmers may use less fertilizer or not apply it
right before it rains. Fertilizer companies could make changes to their product,
which may make it less destructive to an ecosystem. Governments could help
educate people on the dangers of excess nutrients and require farmers to follow rules
that would reduce the amount of fertilizer in run-off or require fertilizer companies
to reduce the harmful chemicals in their fertilizers. Consumers can support farmers
who are actively working to reduce this problem by buying their products.
8. Phosphorous levels decreased from the late 1960s until the early 1980s. From 1985
to the late 1990s, phosphorous levels increased almost to their 1960s levels.

978-0-07-072367-2 Chapter 1 Nutrient Cycles and Energy Flow • MHR TR-1-15

 Section 1.2 The Biosphere and Energy
(Student textbook pages 21 to 27)

Sustainable Ecosystems: In this section, students will learn about the relationship of energy to the biosphere.
Specific Expectations Students will describe photosynthesis and the transfer of energy through trophic levels.
• B2.1 use appropriate Students will also learn how bioaccumulation of certain manufactured toxins have
terminology related to affected bird populations in local ecosystems.
sustainable ecosystems
• B3.2 describe the Common Misconceptions
complementary processes • Students may be under the impression that the boreal and temperate forests
of cellular respiration and
perform the majority of Earth’s photosynthesis. In fact, together they contribute less
photosynthesis with respect
to the flow of energy and than 20 percent, as shown in Figure 1.14, on student textbook page 23.
the cycling of matter within • Students may think that the amount of photosynthesis done by phytoplankton
ecosystems, and explain how provides a buffer that regulates carbon dioxide (CO2) consumption and oxygen
human activities can disrupt
(O2) production on Earth. In reality, this system is at serious risk due to overfishing
the balance achieved by these
processes of large predator species such as tuna, marlin, and shark, which leads to an
overpopulation of smaller species that directly feed on phytoplankton.
• Students may think that toxic chemicals have now been banned and are no longer
in use. Although we often speak of DDT being banned in the 1970s, DDT was not
banned in Canada at the same time as it was in the United States. Rather, it was phased
out in the mid 1970s, registration for use was discontinued in 1985, and it was not
until 1990 that the use of DDT became a violation of the pest control act. While PCB
production was banned across North America in 1977, the use of PCBs is still being
phased out. PCBs are still in use in many electrical applications, such as transformers
and capacitors. There are many other toxins that bioaccumulate in our environment,
which are not yet banned or are only minimally controlled, such as mercury.

Background Knowledge
We tend to focus on humans’ ecological impact on the lives of organisms that we can see,
such as birds. What is neither well studied nor understood is how the ecosystems of our
oceans have a direct impact on humans.
It is estimated that shark populations have declined by almost 90 percent since the
1970s due to overfishing. Sharks are the top predator in the oceans so they directly
control the populations of smaller fish species. Most shark species prey on smaller fish
that are direct consumers of phytoplankton. Therefore, as shark populations decrease,
the populations of smaller fish increase, and the amount of photoplankton decreases
sharply. The food chain that links sharks and photoplankton is very short, and the effects
of any imbalance on oxygen and carbon dioxide levels are felt quickly.
DDT is still in production and in use today in some parts of the world. It is used
to control insect-borne tropical diseases such as malaria. Its use to control the insects
that carry the disease is very controversial, but it can be argued that DDT has helped to
save millions of lives. DDT is fat soluble, so it can build up in fatty tissue, and it causes
the thinning of eggshells in fish-eating birds. The mechanism of human toxicity is not
as well understood, although severe overexposure will have adverse effects, most likely
neurological.
The effect of PCBs on humans is more clearly understood than that of DDT. There
have been more direct links drawn to reproductive and cognitive disorders, as well as
cancer. It is interesting to note that although the production of PCBs has been banned,
the use of PCBs has not yet been banned, likely because PCBs were used as coolant
and lubricant in large transformers that are still in use. Other uses for PCBs have
included plasticizers and pesticide extenders. The disposal of PCBs is extremely difficult.
When incinerated, one of the byproducts is dioxin. Dioxin is one of the most toxic
environmental contaminants known.

TR-1-16 MHR • Unit 1 Sustainable Ecosystems 978-0-07-072367-2

 Mercury still seems to get more coverage in the media than DDT and PCBs, and
students may ask about it. The use of mercury is regulated, but it is certainly not banned.
You can still get dental fillings that have mercury in them, and mercury does enter the
ecosystem naturally. By far, the large majority of mercury entering the food chain is from
atmospheric mercury, the result of burning fossil fuels—coal in particular. The mercury
then enters our waterways as rain and bioaccumulates in fish, including fish that is
caught as food.

Literacy Support
Using the Text
• Preview the Key Terms with English language learners before reading. Discuss
the meanings of the root words synthesis, accumulation, and mass. Draw students’
attention to words they already know that share prefixes with each Key Term, for
example, photo…, bio…). Then have students make connections to predict the
meaning of each Key Term.
Before Reading
• To set students up to make connections to prior learning, use an Anticipation Guide
for this section (see BLM 1-13 The Biosphere and Energy). Students are given a
series of statements related to the section. Before reading the section, students indicate
whether they agree or disagree with each statement. You could read each statement
aloud for English language learners, and allow them sufficient time to process what you
have said, ask questions, and record their answers. Arrange students in pairs to discuss
which statements they agree with and why. Encourage English language learners to ask
their parters for clarification about what is being read aloud, when needed.
During Reading
• Students should have their anticipation guide beside them as they read, to record
corresponding page numbers from the textbook for each statement on the guide.
• Choose some confident readers to read parts of the section aloud for the class.
• To enable less confident readers to participate, pre-assign some short passages for
them to practise before reading aloud.
• ELL Pause the reading at any time to direct students to record an important
point, to discuss a point, to ensure that English language learners understand a
complicated sentence or new term, or to redirect the reading.
After Reading
• Have students make connections to prior learning by revising their agree/disagree
ranking. Students should also correct or revise the statements with which they
disagree. Students can share their revisions with their learning partner. Using mini-
whiteboards, chart paper, or the chalkboard, have each pair of students share one of
their revisions with the class.
Using the Images
• For some students, it is difficult to connect a graphic to an actual cross section. For
Figure 1.12, on page 22, provide students with some actual views of a leaf cross-
section, either by using an LCD projector or by setting up some pre-prepared slides or
microviewers. Have students locate the labelled parts of the leaf cross-section in the
view you provide.
• Have students reconstruct the bar graph from Figure 1.14, on page 23, into two circle
graphs, one showing the percentage of Earth’s surface area, and one showing the
percentage of Earth’s photosynthesis. This task will allow students to internalize the
data and practise their graphing skills. Then have students discuss why the data are
displayed in the textbook as a bar graph.

978-0-07-072367-2 Chapter 1 Nutrient Cycles and Energy Flow • MHR TR-1-17

 • For Figure 1.15, on page 24, have students construct their own pyramids with data
supplied (see BLM 1-14 A Food Pyramid). This activity is designed to walk students
through the process of constructing an Energy Pyramid. To reinforce the concept,
students could complete BLM 1-15 Consumers and Producers, or BLM 1-16
Consumers and Producers (Alternative Version).
• Now that students have had practice constructing Energy Pyramids, have them
construct an upside down pyramid based on the data in Figure 1.16, on page 25,
to illustrate bioaccumulation.
• To reinforce the effect of biomagnification on PCB concentration, students could
complete the calculations on BLM 1-17 Understanding the Mathematics of
Biomagnification.

Assessment FOR Learning

Evidence of Student
Tool Understanding Supporting Learners

Learning Check Students correctly describe the To reinforce the elements in the process of photosynthesis, make
questions, page 23 process of photosynthesis, including several cards, each one with a term to be guessed at the top, and
inputs, outputs, roles of the leaf a short list of words students are not allowed to use when giving
parts, and how it benefits us. clues, below it. Tape a card to each student’s back. Students must ask
their classmates to give clues in order to guess their own word. This
activity will be appealing to the bodily-kinesthetic and interpersonal
learners, as well as helpful for English language learners.
Students can complete supplemental worksheet BLM 1-18
Photosynthesis, to help them organize the inputs, outputs, and
other important elements of the process.

Section 1.2 Review Students explain the process of Create a series of at least 30 cloze (fill-in-the-blank) statements
questions, page 27 photosynthesis (questions 1 and 2) related to photosynthesis and bioaccumulation. Provide students
and its importance (question 3). with a blank bingo template and a list of all the potential answers
Students describe how energy and to the cloze statements. Students will randomly fill in the bingo
contaminants move through trophic template with 24 answers and include a free space in the middle.
levels (questions 5, 6, and 8). When students are ready, choose one cloze statement at a time and
read it aloud. The first student who has five answers in a row yells
“bingo!” and has you check if he or she is a winner.

Instructional Strategies
• DI Provide spatial learners with actual photographs of leaf cross-sections and
plant cells. You can use pre-prepared slides, microviewers, or images from the
Internet. Students should then draw and label their own diagrams from the slides.
• Have students use model kits to balance the photosynthesis equation. Divide the class into
groups of four and provide each group with 6 carbons, 12 hydrogens, and 18 oxygens.
• DI For the logical-mathematical students, make this a problem-solving activity.
Have groups build a glucose molecule, C6H12O6, and then ask them to determine how
many CO2 molecules and water molecules were required to make the glucose.
• DI For bodily-kinesthetic learners, play an abbreviated version of the “Predator
Game.” Use four different colours of tokens to represent four trophic levels. Designate
approximately two thirds of the class primary producers, one quarter primary
consumers, one sixth secondary consumers, and just one or two tertiary consumers.
Give each primary producer 10 green tokens to represent the energy they store
through photosynthesis.

TR-1-18 MHR • Unit 1 Sustainable Ecosystems 978-0-07-072367-2

 • Have primary producers stand, and have direct primary consumers ask the primary
producers for tokens. They may give all or some to each consumer. When all tokens
have been transferred, invite primary consumers to trade the green tokens for white
tokens, which represent the energy they gain by consuming plants, using a ratio of
5 green:1 white.
• Have primary consumers stand, and direct secondary consumers to ask them for
their white tokens. When all tokens are transferred, invite secondary consumers
to trade five white tokens for one red token, to represent the energy they gain by
consuming animals.
• Finally, repeat the exchange with the one or two tertiary consumers asking
secondary consumers for their tokens, then trading five for one blue token.
• Debrief the game by asking students to comment on what represented the energy
transferred through trophic levels, and on what changed as the energy moved up
from one level to the next.
• Enrichment—Have students do some supplemental research on the Internet about
bioaccumulation, or provide students with some articles or websites you have found.
Students can research DDT or PCBs to find out the history, and current locations, of
their use. Once students have done some brief research, divide the class into groups of
four and have students perform quick debates. An example resolution statement could
be the following: Be it resolved that DDT should be banned globally.
• In one style of academic debate, each group of four has two A’s and two B’s. The A’s
take the pro position, and the B’s take con. Each side debates for a maximum time
length of 2 min. English language learners may require some time to prepare the
language they will need for this debate and should have the opportunity to rehearse.
• Once both sides have had a turn, all the A’s gather at one side of the room, and all
the B’s gather at the other side, to share information briefly.
• Have the groups return to their tables, but rotate the B’s around the room so each
pair of A’s is debating with a new pair of B’s.
• Repeat the debates, but this time the B’s are pro and the A’s are con.
• This activity should appeal to the linguistic and interpersonal learners. You can
incorporate a literacy component by asking students to write a short position paper
or letter to the editor voicing their personal opinion after the debate has concluded.
Provide English language learners with sentence starters to use as a scaffold for their
writing. Be sure to offer ample practice to English laguage learners prior to having
them present their positions to others.

Learning Check Answers (Student textbook page 23)

1. Chlorophyll is the pigment that gives leaves their green colour and it uses energy
from the Sun to assemble sugar molecules from water and carbon dioxide in the
process of photosynthesis. Chloros means green and phyllon means leaf.
2. carbon dioxide + water + light energy → sugar + oxygen
Carbon dioxide comes from the atmosphere. Water comes from the soil. Light
energy comes from the Sun.
3. Drawings should include details and labels of stomata. If stomata were damaged, gas
exchange could not occur.
4. During the winter, we continue to be able to breathe oxygen, even though very little
oxygen is being released in Canada from plants. About 30 percent of the world’s
photosynthesis occurs in tropical forests. Wind moves air around Earth, and it is
likely that some of the oxygen we breathe in January in Canada has been generated
by photosynthesis in tropical forests.

978-0-07-072367-2 Chapter 1 Nutrient Cycles and Energy Flow • MHR TR-1-19

 Section 1.2 Review Answers (Student textbook page 27)
Please also see BLM 1-19 Section 1.2 Review (Alternative Format).
1. In the process of photosynthesis, chlorophyll in plant leaves receives solar energy
and uses it to assemble sugar molecules from water and carbon dioxide. Besides
sugar, oxygen is also produced by photosynthesis.
2. The three chemical elements that are the building blocks of carbohydrates are
carbon, oxygen, and hydrogen.
3. Students’ answers will vary, but they should explain how the process of
photosynthesis is crucial to life on Earth because it puts together carbon, hydrogen,
and oxygen to make sugar, which is life’s universal energy supply.
4. A producer is an organism that can make its own food. A consumer cannot make its
own food. Consumers must eat other organisms to get the matter and energy they
need to survive.
5. bunchgrass: 2543 energy units
grasshopper: 254.3 energy units
spotted frog: 25.43 energy units
red-tailed hawk: 2.543 energy units
6. Most of the energy in organisms is used by them to function, some is lost as waste,
and some is lost as heat. Therefore, most energy cannot get transferred to the next
trophic level.
7. Bioaccumulation: the toxins do not harm the organism. Example: a monarch
butterfly ingested toxins from the milkweed that it ate as a caterpillar. The toxins do
not harm the butterfly, but the butterfly would be poisonous to eat.
Biomagnification: the concentration of toxins increases as it moves from one trophic
level to the next, so that the animals at higher levels contain many more toxins, and
may be affected by them. Example: DDT affecting reproduction in fish-eating birds.
Both: processes in which toxins are ingested more quickly than they are eliminated;
result in accumulations of toxins.
8. I would expect the larger fish to have more chemicals in their tissues. The smaller
fish may get some chemicals in their bodies by eating zooplankton. Since the
larger fish eat the smaller fish, they probably have higher levels of toxins due to
biomagnification.

TR-1-20 MHR • Unit 1 Sustainable Ecosystems 978-0-07-072367-2

Section 1.3 Extracting Energy from Biomass
(Student textbook pages 28 to 36)

In this section, students will describe the processes of cellular respiration and Sustainable Ecosystems:
fermentation. Students will identify factors that have contributed to acid rain, and Specific Expectations
explain how acid rain has impacted the viability of selected ecosystems. They will also • B1.2 evaluate the effectiveness
analyze and represent graphically the effectiveness of recycling programs in Ontario. of government initiatives in
Canada, and/or the efforts
Common Misconceptions of societal groups or non-
governmental organizations,
• It was once common practice to remove plants from hospital rooms at night. It was such as Aboriginal communities,
thought that at night, the plants removed the oxygen from the room and produced environmental groups, or student
carbon dioxide. During the day, plants were thought to add oxygen to the room organizations, with respect to an
because of photosynthesis. We now know that the amounts of oxygen and carbon environmental issue that affects
the sustainability of terrestrial or
dioxide produced by the plants are not sufficient to be of any harm or benefit
aquatic ecosystems
to patients.
• B2.3 plan and conduct an
• We also now know that cellular respiration takes place both during the day and at investigation, involving both
night. inquiry and research, into how
• Students often link together the greenhouse effect and ozone depletion. In fact, a human activity affects soil
composition or soil fertility, and,
they are two entirely separate effects. Ozone depletion does not cause global warming,
extrapolating from the data and
and the greenhouse effect does not cause ozone depletion. Ozone in the upper information gathered, explain
atmosphere contributes to the greenhouse effect, but the ozone produced by humans the impact of this activity on
only becomes smog; it does not reach the upper atmosphere. Ozone depletion is the sustainability of terrestrial
caused by CFCs, chlorofluorocarbons, human-made refrigerants, and propellants. ecosystems

• Students may think that landfills will slowly decompose all the garbage and • B3.5 identify various factors
related to human activity that
eventually convert the garbage to soil and useable land. While landfills do slowly have an impact on ecosystems,
decompose some garbage, they are not giant compost sites, which is often the and explain how these factors
assumption. Landfills are intended for long-term garbage storage, while some of the affect the equilibrium and
garbage does break down and produce methane gas. Landfills are designed to “seal” survival of ecosystems
in the waste by covering it in layers of soil, which slows the decomposition by cutting
off oxygen.
• Landfills are designed to be land reclamation projects—a completed landfill is
eventually turned into parkland or a golf course. Problems with leachate usually
prevent landfills from having housing or office space built on them.
• Some students believe that landfills are an untapped source of methane that
until now has been underutilized. There is also some concern that landfills will
not produce significant amounts of methane due to recent green-bin diversion
programs, as there may not be enough organic material to decompose. While
landfills do produce some methane, they are not intended to function as a major
energy source.
• Students may believe that the agreement between Canada and the United States in
the 1980s to reduce acid-rain-causing emissions has caused the significant decrease
in acid rain. However, it is difficult to assess the effectiveness of acid-rain-reduction
programs when many of the major plants and industries responsible for sulfur dioxide
and nitrogen dioxide emissions shut down entirely. It is difficult to say whether the
initiatives that started in the 1980s, or our economic climate, has been responsible for
the reduction in acid rain.

978-0-07-072367-2 Chapter 1 Nutrient Cycles and Energy Flow • MHR TR-1-21

 Background Knowledge
All plants and animals perform cellular respiration. Plants produce glucose from
photosynthesis and animals acquire glucose from consuming plants and other animals.
Energy is produced with the addition of oxygen, and the other product of cellular
respiration includes carbon dioxide. To eliminate the carbon dioxide that we produce
through cellular respiration, we exhale it through our lungs.
Greenhouse gasses include nitrous oxide (N2O), methane (CH4), oxygen (O2),
ozone (O3), water vapour (H2O), and carbon dioxide (CO2). Sources for atmospheric
carbon dioxide include decaying vegetation, volcanic eruptions, exhalations of animals,
deforestation, and the burning of fossil fuels.
There has been extensive scientific debate over the use of biofuels as a supplement
or replacement for fossil fuels. The reasoning behind the debate is that the growing
plants will remove carbon dioxide before they are converted to fuel, which in effect
counterbalances the carbon dioxide emissions when finally burned. Exactly how much
arable land would be needed to produce biofuels is still not clear, and this question has
generated the food vs. fuel debate. Many farmers who should be growing crops to feed
their communities are often more willing to grow crops for biofuels, as they can make
a larger profit doing so. It has been speculated that the increasing interest in biofuel
production has led to a global food shortage. Nevertheless, there have been successful
and balanced programs where the stems and stocks left over from a harvested crop are
turned into biofuel.
Visit www.scienceontario.ca for more information about the Kyoto Protocol and
Canada’s Climate Change Plan.
Landfills are essentially garbage-storage facilities. They are usually lined to prevent
leachate from leaking into ground water. The leachate that develops in landfills contains
many toxic organic compounds, many of which come from household products.
Leachate is usually drained off the bottom of a landfill and pumped into a separate
pond. The Fresh Kills Landfill on Staten Island is reported to be the largest human-made
structure on Earth. The Fresh Kills Landfill is now closed and plans are underway to
convert it into a municipal park.
Ontario regulations have made the collection of methane from new landfills
mandatory.
Damage caused by acid rain costs millions of dollars per year. Some research suggests
that acid rain may also be a contributing factor in asthma, Alzheimer’s, and cancer.

Literacy Support
Using the Text
• ELL To preview the section with English language learners, return to the web you
created at the beginning of this unit. Add ideas for Sections 1.1 and 1.2 to the web, and
introduce the Key Terms for this section, describing how they relate to the concepts
already on the web.

TR-1-22 MHR • Unit 1 Sustainable Ecosystems 978-0-07-072367-2

Before Reading
• To help students connect to prior knowledge, create a K-W-L chart for this section on
the chalkboard.

Topic What I Know What I Want to Know What I have Learned

Respiration
Greenhouse effect
Biomass and fuel
Landfills
Acid rain

• Work with students to fill in the first two columns of their charts, showing what they
already know about each topic and what they want to learn.
During Reading
• Students should fill in the last column for themselves, showing what they have learned
from the textbook. Students may read the textbook alone or aloud in a group. For
some subsections, you may decide to present the information that is in the textbook to
the class yourself.
• ELL Provide English language learners with sticky notes. They can use them to
indicate words or ideas that they do not understand as they read. Later, discuss these
words or phrases with the students.
After Reading
• Have students identify items about which they wanted to know, but to which they did
not find answers in the textbook, and items about which they thought they knew, but
that changed after reading the textbook.
• Students should compare charts with a partner and try to help each other find the
answers to the things about which each student wanted to know.
• Have each pair share with the class one thing they learned, and one thing they still
want to learn.
Using the Images
• Referring to Figure 1.19, on page 29, direct students to create their own graphic
organizer for photosynthesis and respiration. The graphic organizer could take the
form of a concept map. Have students connect the following concepts and terms:
carbon dioxide, green plants, decay, fossil fuel, glucose, animals, oxygen, and water.
The words they should use along the connecting lines would include combustion,
respiration, and photosynthesis.
• For Figure 1.21, on page 30, ask students to describe the correlation between carbon
dioxide concentration and global temperature. Have students use BLM 1-20 Carbon
Dioxide and Temperature, to predict what the values will be in the following 10 and
20 years.
• Ask students to create their own table similar to Table 1.3, Reducing Carbon Dioxide
in the Atmosphere, on page 31, which includes actions they could take at home
and at school to reduce carbon dioxide in the atmosphere. Their tables should
follow the same format as Table 1.3 with a description in the middle column and an
accompanying picture in the right column.
• For Figure 1.24, on page 34, set up a demonstration on the lab bench. Include items
similar to those listed in Figure 1.24 and arrange them in order. Display small amounts
of each substance in beakers and test each one with universal pH paper, or invite a
student to do some of the testing. Ensure that protective gloves are worn, and that
nothing is spilled or splashed.

978-0-07-072367-2 Chapter 1 Nutrient Cycles and Energy Flow • MHR TR-1-23

 Assessment FOR Learning

Tool Evidence of Student Understanding Supporting Learners

Learning Check Answers include an accurate description of Form a value line in the classroom. At one end is “I
questions, page 31 respiration, a link from the Sun to all energy understand the questions completely” and at the other
on Earth, and some effective ideas to reduce end is “I do not understand any of the questions.” Direct
carbon dioxide emissions. students to form a single-file line, with no bunching. When
students have placed themselves along the line, fold the
line in the middle, so that each student is facing another,
as a pair. Now have the pairs explain their questions and
answers to each other.

Section 1.3 Review Answers show an understanding of how Students can complete the flowchart on BLM 1-22
questions, page 36 plants capture energy from the Sun, and how Extracting Energy from Plants, to help them understand
organisms use the energy through respiration, the sequence of events related to extracting energy and
fermentation, or combustion. They also include the environmental effects of combustion.
evidence of the relationship between fossil fuel
combustion, greenhouse gases, and acid rain.

Activity 1-3, The x- and y-axes are labelled correctly. Have students work in pairs or groups of four to complete
Recycling in Ontario, Students have chosen an appropriate scale for the graphs on graphing chart paper. They must agree on
page 32 the x-axis for all the data to fit. every decision the group makes, including how to label the
axes, what scale to use, and how high each bar should be.
Students have chosen to draw two bar graphs
using a different colour for each material. Alternatively, have students work in a computer lab and
complete the graphs using a spreadsheet. Students who
Students’ descriptions of trends are based on
are unsure of the most effective ways to display the data
their graphs and include some speculation
can try different types of graphs. The software should
about why recycling may be increasing or
also take care of scaling the axes for them.
decreasing.

Instructional Strategies
• Ask students to recall “reverse engineering” photosynthesis, which they did in
Section 1.2 using model kits. Arrange students into groups of four and have them
construct all of the molecules for respiration: 1 glucose (C6H12O6), 6 oxygen (O2),
6 carbon dioxide (CO2), and 6 water (H2O). Each group will need one symbol or
token representing an arrow and another symbol representing energy. This activity
should appeal to bodily-kinesthetic and spatial learners. Ensure that students with
these learning styles are distributed among the groups.
• DI To engage logical-mathematical thinking, have students arrange the balanced
equation for cellular respiration on their table. In their notebooks, each student should
write down the equation. Under the equation in their notebooks, students should
create a table to summarize the number of atoms on each side of the equation.

Number of Atoms Left Side Right Side

Carbon
Hydrogen
Oxygen

• DI To engage interpersonal and linguistic thinking, ask students to reflect on

movies or documentaries they have seen, or articles they have read recently about the
environment or global warming. Allow a few minutes for discussion. Then ask
students to create a T-chart in their notebooks with the following title: Myths and
Facts about the Greenhouse Effect. (This chart could be created on chart paper or the
chalkboard). One column of the chart will be for the myths and the other will be for
the facts. Have students record as many points as they can for each column, and then
ask them to trade papers with a partner. The partners can add information or make
corrections to the charts. Trade the papers one more time. Once papers have been

TR-1-24 MHR • Unit 1 Sustainable Ecosystems 978-0-07-072367-2

 traded twice, students should return all papers to their original creators. Have students
share some of the results with the class.
• DI Have linguistic learners create an editorial on alternative fuels. Tell students
that an editorial states a point of view, and then supports it. Show them a couple of
examples from a local newspaper or magazine. Students should compare and contrast
two different fuels and their ability to reduce carbon emissions. Students should also
comment on the social and economical impacts that the alternative fuels could have.
Suggested topics could include biofuel, clean coal, landfill methane, and hydrogen fuel
cells. They can use a copy of BLM 1-21 Alternative Fuels, as a template.
• Conduct a classroom debate about fermentation, methane, and landfills. Allow students
some time to do research on the Internet. English language learners could conduct
research in their first language. Each student should complete a graphic organizer to
prepare for the debate on this topic: Be it resolved that the province should discontinue
the use of landfills for waste management. Allow students to choose their own graphic
organizer such as a Venn diagram, concept map, or T-chart. Conduct a brief and
informal debate after students have completed their graphic organizers. This activity
should appeal to the naturalistic, linguistic, and interpersonal learners.
• ELL Assign Learning Check questions that require less language output to English
language learners. For example, question 3 requires students to list, which is easier
than explaining or describing. Question 4 is more open-ended and will allow students
to share the necessary content knowledge without requiring specific language.
• Enrichment—Have students do some independent research on how scrubbers work
to reduce the amount of acid rain caused by industries. Ask students to complete a
hand-drawn and labelled diagram showing how scrubbers work. Alternatively, bodily-
kinesthetic and spatial learners may prefer to build a model.

Activity 1–3 Recycling in Ontario (Student textbook page 32)

Pedagogical Purpose
Graphing allows students to internalize the information and see relationships in it. By
examining and manipulating the data, students find the information more meaningful.

Planning

Materials Graph paper Coloured pencils

Ruler
Computer lab with spreadsheet software (optional)

Time 20 min

Background
Students should notice that the amount of newspaper recycled had decreased. The
amount recycled depends on many factors, such as that more people rely on alternative
sources for their daily news, and that fewer people are buying newspapers.
Activity Notes and Troubleshooting
• Students can work independently.
• Students may have difficulty scaling the y-axis. Have them look at the greatest number
that they will need to graph. For the first graph, the greatest number is 479 473, so the
scale should go to 500 000.
• The graphs are intended to be bar graphs with three or four bars for each year—one
bar for each material.
• Students can compare bar heights for the same material to identify trends or draw a
line from the top centre of each bar to create a line graph.

978-0-07-072367-2 Chapter 1 Nutrient Cycles and Energy Flow • MHR TR-1-25

 Additional Support
• This activity could be completed in a group using markers and chart-sized graph
paper. Have students work in groups of four, and have one pair of students work on
the first graph, and the other pair work on the second graph.
• ELL Some English language learners may need to see a sample bar graph before
they begin. Refer to Figure 1.27, on page 35. Discuss what the labels should be on the
bar graph that they create, how many bars there might be, and so on.
• Students with weak mathematical or small-motor skills may be more comfortable
using the computer to create the graphs. You may still have to walk them through
setting up and labelling the axes by modelling the process, perhaps by using a
projector.
• If students are using a computer, it will be easy for them to change the graphs from
line to bar for comparison.
Answers
1. Students should notice that the trend for newspapers, tires, and electronic waste
decreased. The data trend for glass, and aluminum and copper, increased and then
decreased slightly. The recycling trend for cardboard and plastic increased.
2. Perhaps fewer people purchase newspapers. Instead they rely on the Internet and
television for news. There has not been a recent surge in computer technology to
cause people any need to upgrade. More people may be purchasing winter tires,
causing both sets of tires to last longer because they are only used for half the
year. Fewer products that are packaged in glass are available in the grocery store.
Manufacturers may be switching to plastic packaging to save transportation costs.
3. The government could pass legislation making it mandatory for all communities
to provide recycling pick-up for all residences. The government could also pass
legislation for all apartment buildings to provide recycling bins for its tenants.

Learning Check Answers (Student textbook page 31)

1. Cellular respiration is a process in which oxygen and sugar are consumed and
energy and carbon dioxide are produced.
2. The greenhouse effect occurs because greenhouse gases trap heat within Earth’s
atmosphere. This effect keeps Earth considerably warmer than it otherwise would
be, allowing life to flourish.
3. Answers will vary, but should include the idea of ways to reduce the use of fossil
fuels, such as carpooling, walking or biking instead of driving in a car, or turning
off lights when you leave the room.
4. The energy used to operate a pen or a keyboard comes from the food we eat. That
food includes energy-containing carbohydrates made by plants as well as additional
energy sources in meals that include meat. Plants used photosynthesis to convert
solar energy into the high-energy molecules of carbohydrates. Energy sources
from meals that include meat came from animals’ consumption of plants (or other
animals that ate plants). The following example is the simplest route to show how
the energy we use to operate a pen or a keyboard is traced back to the Sun:
solar energy from the Sun → carbohydrate energy in the plant → energy available
from the body to operate a pen or a keyboard

TR-1-26 MHR • Unit 1 Sustainable Ecosystems 978-0-07-072367-2

Section 1.3 Review Answers (Student textbook page 36)
Please also see BLM 1-23 Section 1.3 Review (Alternative Format).
1. Two processes that organisms use for energy extraction are fermentation and
cellular respiration.
2. Oxygen is necessary for the aerobic breakdown of sugars.
3. Students’ diagrams should be similar to Figure 1.22, on page 32 of the student
textbook.
4. Humans have released much of the carbon dioxide that had been converted to
biomass by ancient plants in the last 200 years or so (which seems sudden compared
to the millions of years it took to make the carbon dioxide), by burning fossil fuels.
5. Nitrogen oxide and sulfur dioxide are released from burning fossil fuels and from
acids that make precipitation acidic.
6. Since the pH of water in an acidic lake is between 4.0 and 5.0, none of these
organisms would be able to survive.
7. Answers will vary and this question could lead to a debate. Presumably, students
will recognize that they often make purchases based on price (and perhaps quality),
but that as consumers, there may be other considerations based on environmental
values.
8. Commuting by car uses fossil fuels that still produce oxides that tend to make
precipitation acidic. This acidic precipitation can kill trees by interfering with their
uptake of nutrients.

978-0-07-072367-2 Chapter 1 Nutrient Cycles and Energy Flow • MHR TR-1-27

 Plan Your Own Investigation 1-A Fertilizers and Algae Growth
(Student textbook page 37)

Pedagogical Purpose
Students will plan and conduct their own investigation into the effects of fertilizer
on algae growth, with your support and direction. In this investigation, students will
manipulate variables and describe the changes they have observed. This is students’ first
chance to develop important skills related to the investigation. They will build on the
skills they develop here in other investigations and in the Unit Projects.

Planning

Materials Balance Scoop

50 mL graduated cylinder Small funnel
Five 250 mL beakers Liquid fertilizer that contains nitrogen and phosphorus
Algae culture (enough for 5 samples)
(enough for 5 samples) 5 adhesive labels
Distilled water
Marker
BLM 1-24 Plan Your Own, Investigation 1-A Fertilizers and Algae Growth (optional)
BLM G-23 Data Table (optional)

Time 25–30 min for students to write a plan, set up a data table, and have the plan checked by you
10–15 min for each student or group to set up beakers with algae and fertilizer
1 week to monitor the experiment; it would be advisable to start the activity on a Monday.

Safety • Fertilizer can burn sensitive skin, so instruct students not to touch the fertilizer, or provide gloves for students
to use.

Background
This lab is intended to model the process of eutrophication. Nutrient levels in lakes and
ponds increase from agricultural run-off, increasing the algae growth. The excess algae
use much of the oxygen needed for other plants and animals in that ecosystem, causing
them to die.

Activity Notes and Troubleshooting

• If this is the first unit of the year, order the fertilizer and algae early.
• If your school has a pond nearby, you may be able to collect algae from it.
• Read the investigation together. Have students identify the parts of this investigation
that are different from activities within the sections. (There is more analysis and
communication, there is a central question or hypothesis, and there is a chance to
extend the investigation.)
• Designate a space in the classroom where students can leave their experiment and
return to check on it.
• If students decide to apply the fertilizer over several days, set aside time each day for
students to monitor their experiment.
• If the experiment is running over several days, set aside the equipment and materials
for students to measure out their fertilizer as they need it.
• Make sure students understand the difference between dependent and independent
variables, before they write their plans.

TR-1-28 MHR • Unit 1 Sustainable Ecosystems 978-0-07-072367-2

• As you review students’ plans, ensure that they include the following:
• a control beaker (algae with no fertilizer)
• a plan for regular observations
• several different amounts of fertilizer
• a plan to observe and describe the amount of algae present (perhaps describing
colour or opacity)
• If there is a limited supply of beakers, purchase some clear disposable plastic cups,
which can be washed and reused.

Additional Support
• DI Intrapersonal learners can become overwhelmed when the whole class is out of
their seats doing activities. As students set up their experiments, allow a limited
number of groups to set up at a time. Have only one person from each group monitor
the experiment each day. This person can be a different group member each day.
• ELL English language learners may have trouble distinguishing between
independent and dependent variables. Use an example to illustrate the concept with
something students will be familiar with, such as food or drink items.
• For example, a student is purchasing juice bottles for herself and her friends. She
purchases 5 bottles for $1.50 each, and the total cost is $7.50. The independent
variable is the number of drinks purchased, and the dependent variable is the total
cost—it depends on the number of drinks bought.
• ELL To ensure English language learners understand the instructions, have the class
suggest simple verbs to replace the directions in the investigation. For example,
brainstorm could be list, carry out could be do, and analyze could be look at the parts.

Answers
Analyze and Interpret
1. The independent variable was the amount of fertilizer added. The dependent
variable was the algae growth.
2. Students should notice different amounts of algae growing in each beaker.

Conclude and Communicate

3. a. The number of producers would increase, except for deeper plants because the
algae would decrease the amount of light reaching them.
b. Consumers of algae would increase for a short time until the oxygen levels
became too low to support them.
c. The decomposer population would increase as plants and animals start to die off
from the lack of oxygen.
4. Improvements might include the use of a control, and measuring the oxygen content
in the water.
Extend Your Inquiry and Research Skills
5. After brief research, students should record in their notebooks why potassium is
added to fertilizer and be able to answer this question in class. (Among other uses,
it helps with the movement of starches, the formation of proteins, efficient water
use, and efficient use of nitrogen.) On a test, students could be asked to design an
investigation to determine the effects of potassium on plant growth and/or the
ecosystem.

978-0-07-072367-2 Chapter 1 Nutrient Cycles and Energy Flow • MHR TR-1-29

 Inquiry Investigation 1-B The Chemistry of Photosynthesis
(Student textbook pages 38 and 39)

Pedagogical Purpose
In the investigation, students examine the change in pH of a system to provide evidence
of photosynthesis.

Planning

Materials 250 mL beaker Water

Bromothymol solution Drinking straw
2 test tubes with stoppers Test-tube rack
1 sheet black paper Masking tape
2 freshwater plant sprigs (Elodea or a similar species)
BLM 1-25 Inquiry Investigation 1-B The Chemistry of Photosynthesis (optional)

Time 15 min for students to set up plants and test tubes

Unless a strong light source is used, it will take more than one period to see a colour change.

Safety • Students should be cautious to not get the indicator solution on their hands, as it could make them quite ill.
• Students should only blow into the test tube; if they ingest the indicator solution, they will become extremely ill.
• Students should wear goggles and aprons to avoid splashing in their eyes and spilling on their clothes.

Background
Bromothymol solution is yellow when the pH is below 7, indicating an acidic solution,
and blue when the pH is above 7. Students’ breath forms a weak acidic solution. The
evidence of photosynthesis occurs when the plants use the carbon dioxide in the water,
moving the pH back to 7 and changing the indicator back to blue.

Activity Notes and Troubleshooting

• Elodea can be ordered from a local aquarium store. Because the demand for Elodea is
seasonal, call the aquarium store well ahead of time to order it.
• Hornwort will work as well as Elodea, and it is a more durable plant.
• Depending on the availability of plant material, this activity should be done in groups
or possibly as a demonstration.
• A very strong light source is needed; use a grow light on a plant stand. If a grow light is
not available, this activity may take a full day.
• Large test tubes are preferred to accommodate the plants. Larger test tubes can be
supported by an Erlenmeyer flask.
• Any indicator that changes around pH 7 will work, including phenolphthalein and
bromocresol purple.

TR-1-30 MHR • Unit 1 Sustainable Ecosystems 978-0-07-072367-2

Additional Support
• Some students may wonder where these plants are used outside of the classroom. They
are used most often in aquariums and backyard ponds to help oxygenate the water.
• ELL Appoint a confident reader to work with each English language learner. English
language learners may wish to prepare a time line, a poster, or another product instead
of a report in Extend Your Inquiry and Research Skills step 8.
• When students use straws, they are usually drinking. Demonstrate blowing bubbles
with the straw, only touching your mouth to the dry end so as not to have any contact
with the solution.

Answers
Analyze and Interpret
1. The gas added was carbon dioxide.
2. The gas created weak carbonic acid when mixed with the water. Acidic conditions
change the colour of the blue indicator to yellow (when bromothymol solution is
used).
3. In the uncovered test tube, students should have observed the indicator solution
change back to blue. In the covered test tube, the indicator solution should have
remained yellow.
4. In the uncovered test tube, the plant was able to perform photosynthesis and use the
carbon dioxide in the water, therefore, changing the pH. In the covered test tube, the
plant was unable to perform photosynthesis.
Conclude and Communicate
5. The control was the test tube covered with black paper.
6. Students’ sketches should indicate carbon dioxide being exhaled by humans,
absorbed by the water, and then consumed by the plant during photosynthesis. The
sketch could also include the plant expelling carbon dioxide into the water during
cellular respiration.
Extend Your Inquiry and Research Skills
7. An extension of this lab could be to investigate how much light exposure the plant
needs to consume the carbon dioxide. Students could cover several test tubes
containing plants and expose each one to different amounts of light. Students should
be able to clearly write out the procedure, and be given enough time to conduct their
inquiry, if possible.
8. Students will require time to research in the library and on the Internet. They should
be able to produce a one-page report on one of the scientists listed.

978-0-07-072367-2 Chapter 1 Nutrient Cycles and Energy Flow • MHR TR-1-31

 Inquiry Investigation 1-C Soil-water Acidity and Plant Growth
(Student textbook pages 40 and 41)

Pedagogical Purpose
This inquiry allows students to investigate how human activity affects soil fertility. In this
case, students are investigating the effects on plants of different acidity levels, resulting
from acid rain.

Planning

Materials 5 small plastic or paper cups Pencil

Marker 500 mL potting soil
Tray 50 mL graduated cylinder
Ruler
5 stoppered Erlenmeyer flasks, containing water with pH levels of 3, 4, 5, 6, and 7
5 seeds (such as beans, radish, or Brassica)
Grow light (optional)
BLM 1-26 Inquiry Investigation 1-C Soil-water Acidity and Plant Growth (optional)
BLM G-23 Data Table (optional)

Time 1–2 h of preparation by the teacher

15 min for students to plant and water the seeds, and to place the cups on the trays
2–4 weeks to complete the investigation
5 min each day to water, and to record growth

Safety • Students must wear safety goggles and acid-resistant gloves. A lab apron is also recommended to protect
clothing.
• Acid solutions should be stored in a fume hood or acid cabinet when not in use.
• Always pour acid into water, instead of the reverse.

Background
While acid rain contains sulfuric acid, it is will be easier for teachers to control the pH
of their solutions using hydrochloric acid or acetic acid.

Activity Notes and Troubleshooting

• Start this activity early in the unit, preferably in the first or second week, in order to
allow enough time for students to observe growth.
• Order seeds early, and purchase potting soil that has not been augmented with fertilizer.
• Prepare enough pH solution for students to water daily for at least two weeks, possibly
three weeks. Each group will require approximately 150 mL of each solution.
• To prepare pH solutions, start with a solution of pH 3. Each subsequent pH is a
dilution by a factor of 10. Use hydrochloric acid or acetic acid to prepare the solutions
(they are monoprotic acids). A concentration of 0.001 mol/L will result in a pH of
3, 0.0001 mol/L will result in a pH of 4, and 0.00 001 mol/L will result in a pH of 5.
Continue in this fashion until all of the solutions are prepared, and test each solution
with a pH meter or indicator paper before dispensing. Clearly label, date, and initial
the prepared solutions. If you prepare 2.5 L of pH 3, then you can use 250 mL of that
solution to create 2.5 L of pH 4, and use 250 mL of the pH 4 solution to create 2.5 L
of pH 5 solution, and so on.

TR-1-32 MHR • Unit 1 Sustainable Ecosystems 978-0-07-072367-2

• Take care in preparing the acid solutions. Wear proper safety equipment including
goggles, acid-resistant gloves, and a lab coat. Always pour acid into water. If you are
unsure how to dilute stock solutions, ask your department’s chemistry teacher for
assistance.
• Set aside an area of the classroom for students to conduct the lab; a plant stand with
grow lights may be required.
• Have students work in pairs or groups, depending on the space and resources available.
• The procedure for preparing the plants is straightforward. Have a student read each
step aloud as you demonstrate the step to the class.
• Radishes grow very quickly and provide the best results. If radishes are unavailable,
black oil sunflower seed (from birdseed) will grow fairly quickly.
• Some plants will die prematurely. It may be acceptable for groups to merge or share
data if this happens. Students will need enough data to analyze and make predictions.
• To conserve space in the classroom, save garden centre cell packs from your own
gardening for students to start their plants in. Students can label the plants with
craft sticks.
• It will be safe for students to take home plants grown in pH 6 or 7.

Additional Support
• Some students will become upset when their plants die, especially if they die
prematurely or fail to germinate at all. You should have your own set of plants as
backup, or allow groups to merge to ensure enough data are collected.

Answers
Analyze and Interpret
1. Answers will vary depending on results.
2. Radishes prefer a pH of 6.5 or higher for optimal growth. Students should have
recorded the best results for pH 7, but may have seen good results for pH 6 as well.
Conclude and Communicate
3. Students’ statements should reflect their results, and will most likely state that lower
pH inhibits the growth of radishes. Please note that some plants prefer slightly acidic
soils, including some types of berries.
4. Students’ results should support the hypothesis that plants will grow best in neutral
soil and not grow as well in soils with more acidity. If their results do not support
their hypothesis, they must have hypothesized a different relationship, for example,
that more acidity would lead to greater growth, or that more acidity would have
no effect.
Extend Your Inquiry and Research Skills
5. Students could collect rain in the schoolyard and at their home and bring it into the
classroom to test with universal pH paper. They should record the pH from several
different rain events over a month. Ask, “Does the pH change on different days?”
“What could be an explanation for your area?”
6. Students could conduct research in the library and on the Internet to identify the
effects of rocks in neutralizing acid rain. Students could write a one-page report or
fact sheet summarizing their findings.

978-0-07-072367-2 Chapter 1 Nutrient Cycles and Energy Flow • MHR TR-1-33

 Plan Your Own Investigation 1-D
Can a Plant Have Too Much Fertilizer? (Student textbook page 42)

Pedagogical Purpose
Based on what students have learned in this chapter, they should be able to make some
predictions about the effects of fertilizer on plant growth. This activity provides an
opportunity for students to design their own investigation, with teacher support, to
support or refute their predictions.

Planning

Materials 5 green pea seeds 3–5 large cups

750 mL soil Garden trawl
Marker Water
Fertilizer that contains nitrogen (enough for 3–5)
Soil test kits for nitrogen
BLM 1-27 Plan Your Own Investigation 1-D Can a Plant Have Too Much Fertilizer? (optional)

Time 15 min to create the data table and have a plan approved by you
20 min to plant the seeds
10 min to prepare the fertilizer
5 min daily to monitor the plants
2–4 weeks to collect the data

Safety • Fertilizer can burn sensitive skin. Students should wear goggles and gloves when handling fertilizer.

Background
Fertilizer run-off from our lawns and farms is the major contributor to eutrophication.
However, without fertilizer, we would not be able to grow enough food to support
the current population of our planet. Plants will thrive within a range of fertilizer
concentrations. Too little and they will not get enough nutrients. Too much and they will
be damaged by the chemicals in it.

Activity Notes and Troubleshooting

• Teachers should start this activity early in the unit so students have enough time to
collect and analyze the data.
• Purchase soil that has not been augmented with fertilizer.
• Set aside an area in the classroom for students to conduct the experiment and
monitor it.
• You may want to start the seeds under a damp towel first; then students can plant the
seeds that have germinated.
• Remind students that they should have a control as part of their plan.
• Students have a tendency to over-fertilize all of their specimens at the beginning, and
then have no results at all. Read the directions on the fertilizer and the seed packages
to determine the recommended amount. Have students try more than, and less than,
this amount.

TR-1-34 MHR • Unit 1 Sustainable Ecosystems 978-0-07-072367-2

Additional Support
• ELL Write the terms dependent variable, independent variable, and control on the
chalkboard. Discuss the meaning of each term, and record a definition or example
beside each one.
• Students have a tendency to take plant mortality too seriously. If their plants die
prematurely, students take this death as a personal failure. Allow enough time for
students to start over if their plants die too early to collect enough data.
• Allow groups to merge or share data if some plants die early.

Answers
Analyze and Interpret
1. Answers will vary depending on students’ results.

Conclude and Communicate

2. Too much fertilizer will have the opposite effect of what was intended. The fertilizer
could run off and cause damage to surrounding gardens and ecosystems.
3. The trees could experience an unseasonable burst in growth; however, if too much
fertilizer ran off, the roots could be burned and the tree would die.
Extend Your Inquiry and Research Skills
4. Students should be able to write the procedure for an investigation using compost
instead of fertilizer. Students may also want to compare compost to fertilizer.
Conducting this investigation may not be practical for all students, as they may not
have composters at home. All students should be able to write a procedure for this
type of inquiry, however.

978-0-07-072367-2 Chapter 1 Nutrient Cycles and Energy Flow • MHR TR-1-35

Chapter Review Answers (Student textbook pages 44 and 45)
Please also see BLM 1-28 Chapter 1 Review (Alternative Format).

ELL Consider asking English language learners to group 9. A sustainable ecosystem endures and supports, which
the review questions. Have the students pick the questions means it maintains the same condition for a long period
that they feel they can answer independently. Then have them of time and supports various different organisms.
select the questions for which they are not sure of what they 10. Aquatic ecosystems are responsible for 30 percent of the
are being asked. Clarify these questions by restating them. Let world’s photosynthesis to produce oxygen. Animals in
students select the questions for which they may need some terrestrial ecosystems depend on this oxygen to survive.
language support, and finally, those questions for which they
11. Organisms, such as plants, which can make their own
need peer support or reteaching.
food, are called primary producers. They are at the first
Make Your Own Summary trophic level within the biosphere, are the only organisms
that can produce sugar to store the Sun’s energy, and are
Nutrient Cycles therefore important for all other organisms to survive.
and Energy Flow
12. Step 1: the Sun
Step 2: evaporation
Step 3: condensation
Sustainability Extracting Energy The Biosphere Step 4: precipitation
from Biomass and Energy
Step 5: run-off
Arrows should follow a cycle through Steps 2, 3, 4, 5,
Sustainable The biosphere relies on Organisms use cellular
ecosystems endure and a constant stream of respiration to extract and 2 again.
sustain the organisms solar energy. the energy stored in
that live within them. the sugar produced by 13. The Industrial Revolution resulted in an increase in the
photosynthesis.
burning of fossil fuels—such as coal, petroleum, and
natural gas—as a source of energy. Burning these fossil
Matter, including Chlorophyll in primary Burning fossil fuels has
nutrients such as producers converts solar dramatically increased fuels adds carbon dioxide to the atmosphere.
nitrogen, is constantly energy to chemical the concentration of
moving through Earth’s energy through carbon dioxide, a 14. Fossil fuels are decomposed plant and animal matter. The
spheres. photosynthesis. greenhouse gas, in the energy stored in fossil fuels comes from the photosynthesis
atmosphere.
that the plants underwent when they were alive.
Human activities that Most of the stored Acid precipitation is 15. Cellular respiration takes place when oxygen is present;
increase the flow of energy in one trophic caused by burning
nutrients into an level does not move to fossil fuels. It can have
fermentation takes place where oxygen is not present.
ecosystem can upset the next trophic level. negative effects on
the nutrient balance in terrestrial and aquatic 16. a. Three examples of greenhouse gases are water vapour,
the ecosystem. ecosystems. carbon dioxide, and methane.
b. Greenhouse gases increase the temperature of the
Decisions and actions Bioaccumulation and Increased awareness
to protect the health biomagnification can and improved atmosphere by trapping heat. Earth would be much
of ecosystems may result in unhealthy technology have led colder without greenhouse gases in the atmosphere.
involve international levels of pollutants in to a decrease in acid
agreements and court organisms. precipitation since the The increased burning of fossil fuels in the last few
decisions. 1980s.
centuries has released a lot of carbon dioxide in the
atmosphere, and many scientists believe that this
Reviewing Key Terms
increase has led to problems such as global warming.
1. biosphere
17. a. The Kyoto Protocol is an agreement signed by over
2. eutrophication
180 countries to reduce greenhouse gas emissions.
3. ecosystem Countries are encouraged to reduce emissions or to
4. photosynthesis plant trees in non-forested areas to remove carbon
dioxide from the atmosphere.
5. trophic level
b. Through government initiatives, countries can reduce
6. cellular respiration carbon dioxide in the atmosphere by reducing gas
7. greenhouse effect emissions, planting trees, protecting existing forests,
and recycling.
Knowledge and Understanding
8. Interacting parts of a biological community and its
environment are called an ecosystem.

TR-1-36 MHR • Unit 1 Sustainable Ecosystems 978-0-07-072367-2

Thinking and Investigation 26. It does not matter where in the atmosphere the gases
18. Students’ examples will vary. Example: The Brock West are released. Nitrogen oxide and sulfur dioxide combine
Landfill Site in Pickering, Ontario, collects and uses with water in the atmosphere, producing nitric acid and
methane gas to generate electricity. sulfuric acid. The acids can travel far in the wind and
19. Students’ answers will vary but might include the following: will eventually fall back down to Earth’s surface in the
using vehicle transportation to get to school (petroleum); form of precipitation.
using electricity for lights, heat, air conditioning (coal, oil, 27. The greenhouse effect is produced by greenhouse gases
and gas); and using manufactured product like cellphones, warming Earth by trapping energy. The enhanced
food packaging, and so on (coal, oil, and gas). Instead, greenhouse effect is produced by humans adding too
students might walk, cycle, or carpool to school; turn off many greenhouse gases to the atmosphere, possibly
lights in rooms that they are not using; turn down the heat resulting in global warming.
or the air conditioning; and try to buy products that have
Application
less packaging.
28. An animal living far away from an area sprayed with
20. To reduce the emissions of sulfur dioxide and nitrogen DDT might get DDT in its body through the processes
oxide, individuals can ensure their cars meet the motor- of bioaccumulation and biomagnification. It might eat
vehicle emissions tests. Students may also mention that contaminated birds or fish that travel great distances.
they can walk, cycle, carpool, or take public transit; they
29. If a pesticide is stored in the body of an organism and
can travel by air as little as possible; and they can buy
remains toxic for many years, it can be passed on to other
products that were produced locally.
organisms for years to come. Instead, it would be better if
Communication pesticides were easy to break down and dispose of.
21. Students’ diagrams should be similar to Figure 1.6, on 30. Eating a plate of rice and vegetables would make you
page 16 of the student textbook. Their diagrams should a primary consumer, because primary consumers are
show that nitrogen is converted to usable forms, such as herbivores and eat only plants. Eating a hamburger
ammonium and nitrate, which are absorbed by plants. would make you a secondary consumer, since you would
Organisms then eat the plants and use the nitrogen in be eating part of a cow, which is a primary consumer.
their bodies. Excess nitrate and ammonium enter the
lithosphere and become part of rocks. It does not return
to the atmosphere for many centuries. Students should
also show that fertilizer is a human factor that alters the
balance of nutrients.
22. Students’ e-mails will vary but should include the idea
that trees and plants absorb carbon dioxide from the
atmosphere and produce oxygen, so protecting forests
and planting new trees is important.
23. first trophic level: Phytoplankton are primary producers.
second trophic level: Zooplankton are primary consumers.
third trophic level: Crabs are secondary consumers.
fourth trophic level: Sea otters are tertiary consumers.
24. Students’ diagrams should be similar to Figure 1.3, on
page 13 of the student textbook, including placing the
biosphere all around everything.
25.

Reaction Photosynthesis Cellular respiration

Organisms in Which Reaction Occurs Plants, algae, some bacteria Plants, animals, fungi, other organisms

Reactants Carbon dioxide, light Oxygen, sugar

Products Oxygen, sugar Carbon dioxide, water

Is Energy Absorbed or Released? Absorbed Released

978-0-07-072367-2 Chapter 1 Nutrient Cycles and Energy Flow • MHR TR-1-37

 Chapter 2 Populations and Sustainable
Ecosystems
Materials In this chapter, students will learn that populations will increase until they reach their
Please see the teaching notes carrying capacity, and that specific factors will affect the carrying capacity. Students will
for each activity for a list of the be able to explain that no two species can occupy the same niche. Students will also be
materials required. Please see able to describe services that many species provide to other members of an ecosystem.
page TR-35 for a summary of the
materials required in this chapter
Using the Chapter Opener (Student textbook pages 46 and 47)
and other chapters.
• You might poll students and ask how many have seen an owl in the wild. Ask, “What
Advance Preparation did the owl look like?” “If it was flying, what sound did it make as it swooped by?”
• Compile a list of as many (Their wings make a distinctive whoop-whoop sound.)
indigenous species of animals
in Ontario as there are students
• Ask, “What else might owls eat?” (A large owl can eat an average-sized house cat.)
in your class. Students can each • Ask students where they think the photograph on pages 46 and 47 was taken: on a
choose one species to research
farm, in the forest, or in a park. Can they tell what season it is from the picture?
in section 2.1.
• Book a computer lab for Activity Alternatively, focus on an often overlooked service that local forests provide. Many of
2-2, on page 52 of the student us are happy to know that the forest still exists somewhere in the province providing
textbook. habitat for wildlife. We may not realize the importance of our local urban and suburban
• Order owl pellets for Activity forests in regulating rain and meltwater run-off. The deep roots of trees allow water to
2-3, on page 60 of the student percolate down through the soil, often to be stored in underground aquifers. Many of
textbook. us draw our water directly from these aquifers using wells. Others draw our water from
• Field guides to birds of Ontario rivers or lakes, ultimately fed by streams and springs that originate from the ground.
will be useful to have in the Water that reaches aquifers is naturally filtered and often stored for years. It is local trees
classroom in section 2.4.
that provide this service. For example, local woodlots and small tracts of forest on the
• Order butterfly chrysalis kits, Oak Ridges Moraine provide clean water for the Greater Toronto Region. Unfortunately,
if you wish to use them in
the proximity of these pockets of forest to the city make them highly appealing for
section 2.4.
development.
• Consider beginning Inquiry
Investigation 2-B, on page 80
Activity 2–1 Reducing Wildlife Mortality with Fences
of the student textbook, early
(Student textbook page 47)
in the chapter, as it will take
three weeks to complete. Pedagogical Purpose
• Students can review the Key This activity provides students with an opportunity to examine how human activity has
Terms in Chapter 2 using made an impact on an ecosystem, specifically wildlife.
BLM 2-1 Chapter 2 Key Terms.
Planning

Materials Chart paper and markers (optional)

Time 15 min

Background
The controversy with fencing is that it intersects wildlife habitat, possibly reducing the
amount of habitat normally available to an individual. When we consider fencing of
highways, we also must consider ways for animals to safely get to the other side, which
may be in the form of tunnels or underpasses.
Activity Notes and Troubleshooting
• Get students up and moving as they engage their prior knowledge:
• “Stand up and stay up if you have
• driven through Algonquin Provincial Park.
• seen fencing along park roads.
• seen animals from your car while driving.
• seen a dead animal on the road or by the road.”

TR-1-38 MHR • Unit 1 Sustainable Ecosystems 978-0-07-072367-2

 • By this time, most of your class will be standing. Then ask them to sit down and
discuss with a classmate how they felt or how they would feel about seeing dead
animals on the road.
• The graph in this activity is more complex than most students will be used to. Before
students begin the activity, read the introduction together and display the graph
for all students to see, if possible. Then ask questions to ensure all students come to
understand the many features of the graph, such as the following:
• Is this a bar graph or a line graph?
• Which axis tells us about the bar graph? Which axis tells us about the line graph?
How do you know?
• Why are there two bars for every year?
• What do first fence and second fence mean? (They refer to the first section of fenced
road, and the second section of fenced road, where data were gathered.)
• Teachers in urban areas could ask students which animals are often in roadside
collisions within a city, and what can be done to prevent these types of collisions.
Additional Support
• ELL Preview the vocabulary in this activity with English language learners. Words
like mortality, traffic, annual, vehicle, and others may be new to some students. Explain
what the Trans-Canada highway is and/or show pictures of animals commonly seen
near a road. English language learners could answer orally or in point form.
• Some students will need additional support to interpret the graph. Discuss with
students some of the information that the graph shows. For example, ask students why
the light bar for most years might be taller than the dark bar.
• DI Pair logical-mathematical learners with others to ensure students are able to
obtain the information that they need from the graph.
Answers
1. The mortality rate along both sections started around 30. The rate for the first
section then dropped in 1987 and has remained around 10. The rate for the second
section jumped to more than 90 in 1988, then decreased to also settle around 10.
2. The amount of daily traffic increased steadily until it had almost doubled in value.
3. Probably because the current mortality rates are less than the original values, even
though daily traffic has nearly doubled.
4. It is a good indicator of the impact humans have on wildlife.

Study Toolkit

Strategy Page Reference Additional Support

Making Student textbook pages 49, 54, 75 Have students fold a piece of paper into four parts and number
Connections each part to record their answers to the questions on page 48.
to Visuals

Base Words Student textbook page 62 (mutualism), Refer students to Study Toolkit 3, Word Study: Common Base
page 63 (parasitism), page 70 (desertification, Words, Prefixes, and Suffixes in Science, on page 565 of the
watershed), and page 76 (connectivity) student textbook.

Interpreting There are many line graphs in this chapter for Following the procedure to create a line graph in Math Skills
Line Graphs students to interpret, including on pages 49, Toolkit 3, on page 557 of the student textbook, will help
51, 58, 59, 60, 66, 70, and 74. students build an understanding of the different parts of a
graph and what we can learn from each part. See also BLM G-25
Constructing a Line Graph and BLM G-26 Interpreting Line
Graphs.

978-0-07-072367-2 Chapter 2 Populations and Sustainable Ecosystems • MHR TR-1-39

 Section 2.1 Populations and Resources
(Student textbook pages 49 to 55)

Specific Expectations In this section, students will learn about patterns of population growth for a variety of
• B1.1 assess, on the basis of species, including humans. Students will describe the factors that limit an ecosystem’s
research, the impact of a factor carrying capacity. They will learn how the human population has been able to grow
related to human activity that exponentially by manipulating the carrying capacity of Earth. Students will understand
threatens the sustainability of a
how urban sprawl has affected the populations of local wildlife as well as how humans
terrestrial or aquatic ecosystem
have been successful at re-introducing some species.
• B3.3 describe the limiting
factors of ecosystems, and
Common Misconceptions
explain how these factors affect
the carrying capacity of an • A population will increase exponentially to fill in a new habitat. This is true at
ecosystem first; however, students may not realize that a population can increase too rapidly and
• B3.5 identify various factors “overshoot” the carrying capacity of an area, which then leads to rapid population
related to human activity that decline.
have an impact on ecosystems,
• Students may believe that re-introduction of a species results in a return to a
and explain how these factors
affect the equilibrium and balanced ecosystem. In fact, species re-introduction cannot go unmonitored, and
survival of ecosystems human intervention is often required to maintain population stability. As one species
disappears from its habitat, so do its natural predators. For example, wild turkeys were
successfully re-introduced into southern Ontario. While the wild turkey population
of southern Ontario is no longer threatened, their story is not entirely successful.
Ottawa-area farmers have complained that the turkey population is interfering with
their crops. There is some evidence that the wild turkey population did not extend this
far north originally, and the turkeys have now expanded into areas where they never
existed before.
• Students may think that initiatives, such as the Oak Ridges Moraine Conservation
Act, are innovative ideas to protect southern Ontario’s fragile ecosystems. In
fact, the Oak Ridges Moraine Conservation Act compliments the Greenbelt Act of
2005. The desire to create a zone surrounding the Greater Toronto Area and Golden
Horseshoe, which is exempt from commercial and residential development, dates
back to the 1970s. There is not much undeveloped land left from the Greenbelt that
was originally envisioned at that time. The Oak Ridges Moraine Conservation Act and
Greenbelt Act are the last stand to try to protect the green space that is left.

Background Knowledge
Not all re-introductions of endangered species are successful. While the genetics of the
species are preserved, the survival techniques that must be taught by parents are not
passed on. There is also a possibility that the re-introduced animals will be too familiar
with humans, which could be dangerous.
There has been much controversy over the re-introduction of wolf populations to
eastern North America, including Algonquin Park. The original species of wolf was most
likely the red wolf; however, red wolves interbreed too easily with feral dogs and coyotes,
increasing the chances of negative human interaction. Wolves keep the deer populations
in the eastern forests at healthy numbers, so grey wolves were chosen for re-introduction
as they are far less inclined to interbreed outside their species. Grey wolves are larger
than deer, however, and are more efficient hunters, so there is a chance that they could
decimate the deer population. Therefore, both populations are being carefully monitored.
Southern Ontario’s wild turkey re-introduction has been so successful that the turkey
population has now expanded beyond its original boundaries. When the wild turkey was
re-introduced, some of its natural predators were long gone from the area. To keep the
population under control, the Ontario government has had to expand the turkey hunting
season to include both fall and spring.

TR-1-40 MHR • Unit 1 Sustainable Ecosystems 978-0-07-072367-2

Literacy Support
Using the Text
Before Reading
• Have students skim the section, focussing on the headings, Key Terms, and visuals
and captions, to predict the main ideas and to develop definitions of the Key Terms.
Discuss the meaning of each term, and have students share where they found the
information to help them understand each term.
• ELL Display definitions in students’ own words for English language learners to
refer to throughout the section and the chapter.
During Reading
• Place students in groups of five or six, and assign each member of the group a passage
to read.
• ELL Choose the length and complexity of the passages you assign based on
students’ reading abilities.
• Allow each group time to share the information that they have read. Students can
take turns and verbally summarize their passage for the rest of the group. Others in
the group can ask questions.
After Reading
• Students can respond to their reading by participating in a “graffiti” activity.
Emphasize to students that graffiti is an expression of personal thoughts and feelings.
• Give each group markers and a piece of chart paper with a statement or question
in the middle, and ask students to respond to that statement. After three to five
minutes, each group will pass their paper to an adjacent group until all the groups
have responded to all of the statements.
• The statements can come from the Section 2.1 Review questions on page 55 of the
student textbook.
• Exponential growth is not sustainable in nature.
• Limited resources will affect the growth of a population.
• Carrying capacity can be manipulated with positive and negative outcomes for
different populations.
• Intensification can limit the human impact on wildlife populations and habitats.
• When the groups have responded to all the statements, and their original statements
have been returned to them, each group will select the three most interesting or
important responses. They can then write the page numbers of the information in
the student textbook to which each response relates. Then each group can present
their question and three statements to the class.
• All students in the class should record the question and statements presented
by each group, with the corresponding student textbook page numbers, in their
notebooks. Each presenting group could circle the three statements they selected
and display the chart paper for others to copy at their own pace.

Using the Images

• For Figure 2.1, on page 49 of the student textbook, ask questions to ensure everyone
understands what the graph shows, and then ask students to predict what the
elephant population is today, and explain what led them to that conclusion. Some
students may extend the graph and predict millions of elephants, and some may
rationalize that the population will eventually level off.
• For Figure 2.2, on page 50, have students describe the habitat requirements of the
turkey that are suggested in the picture. For example students may mention open
fields next to forest.

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 • Have a volunteer describe the graph in Figure 2.5, on page 51, and then ask students
why the fur seal population did not continue to grow after 1935. Ask, “How would
the line change if hunting were to increase, or if habitat were to decline?”
• Compare the two maps from Figure 2.6, on page 52, and Figure 2.7, on page 53.
Ask students to explain why the remaining dace are found where they are. Students
should notice a slight correlation between the green areas shown in Figure 2.6,
and the redside dace populations shown in Figure 2.7. Ask students if they think
the population is increasing or decreasing, and what we can do to protect the
population.
• For Figure 2.8, on page 54, ask students to brainstorm ways to increase human
population density other than building higher. The answers can be recorded on the
chalkboard for students to copy into their notes. Answers may include the following:
divide houses into apartments, build on undeveloped and abandoned land in the
city, re-purpose abandoned land and buildings, place parking underground, or
provide less parking.

Assessment FOR Learning

Evidence of Student
Tool Supporting Learners
Understanding

Selected Response Students describe the relationship Arrange the class into groups of four for Pass, Pass, Trade: Assign
Learning Check between population growth and each student in a group a different question to explain. Have each
questions, page 51 limits. student explain his or her question and answer to a partner, using
written notes and diagrams as appropriate; the partner does the same.
When both are confident that the other understands his or her question
fully, they trade cards, papers, or white boards, and repeat the process
with a new partner. Continue in this manner until all students in the
group have heard and explained all the assigned questions.

Section 2.1 Review Students explain relationships Ensure that students understand the Key Terms in each question.
questions, page 55 among population growth, limits, Students can label graphs or sketch and label graphs instead of writing
and carrying capacity, and provide sentences for many of the answers. Refer to Figure 2.1, on page 49,
examples. to see how a labelled graph can provide an explanation of population
trends.

Performance or Students are able to accurately Demonstrate how to draw a line of best fit. On the chalkboard, plot 16
Product represent the data on a graph points, Model how to select the position for the line; an equal number
Activity 2-2, by selecting the appropriate of points should be on either side of the line. Lines of best fit do not
Graphing Population scales, drawing a line of best fit, have to be straight. Plot new points, and invite students to trace a line
Change, page 52 and extending the line to make of best fit with their fingers and tell why they would draw it where they
predictions for the year 2020. indicated.
Refer students to the Math Skills Toolkit 3, on pages 557 to 560 of the
student textbook.
Students can practise with BLM G-25 Constructing a Line Graph and
BLM G-26 Interpreting Line Graphs.
Students can use spreadsheet software to plot the points, but they
should draw their best-fit line on their own.
Students should draw three separate graphs, selecting different scales
for the y-axis so that the data fill most of a page. In this way, they will
be better able to extrapolate the data.

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Instructional Strategies
• To introduce this section, talk about an animal whose population changes are familiar
to some students, for example the elephant (after reading page 49 of the student
textbook). As you talk about it, sketch a rough line graph and label the parts of the
graph that show its decline, exponential growth, protected status, equilibrium, and so
on. Leave this graph on display for students to refer to.
• Data Analysis Investigation 2-A, on page 79 of the student textbook, provides students
with opportunities to apply what they have learned as they draw and interpret a graph
to draw conclusions about the winter skate population in Nova Scotia.
• Enrichment—Using one of many available web resources, assign each student in the
class a different animal indigenous to Ontario. To find information about indigenous
animals, see www.scienceontario.ca.
• DI Have each student prepare a fact sheet outlining the habitat requirements for
their animal. The fact sheet should include where the animal is found in Ontario; its
estimated population; who its predators, prey, and competitors are; the limiting
factors for its survival; and whether the animal is at risk or endangered. Students
can create their fact sheets on BLM 2-2 Ontario’s Indigenous Animals. This
activity will appeal to linguistic and logical-mathematical learners.
• DI Spatial learners could also create a letter-sized poster depicting the animal in
its habitat, illustrating some of the points on the fact sheet.

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 Activity 2-2 Graphing Population Change (Student textbook page 52)
Pedagogical Purpose
Students will assess the impact of urban sprawl on bird populations by graphing and
interpreting the data provided for a 12-year period.

Planning

Materials 3 pieces of graph paper Ruler

Coloured pencils Computer lab (optional)
BLM G-25 Constructing a Line Graph (optional)
BLM G-26 Interpreting Line Graphs (optional)

Time Total: 50–60 min

Background
Mourning doves are related to pigeons. Students may notice that the population of
mourning doves increases, which is because suburbia and backyard feeders provide an
ideal habitat for these birds.
Downy woodpeckers are not bothered by human activity as much as other species
are, and they can be found at backyard feeders. When surrounding forests reach
maturity, they provide optimal habitat for woodpeckers (from old and dead standing
trees).
After 1999, much of the forest surrounding Barrie was cut down to accommodate
a housing boom. Ruffed grouse are very sensitive and reclusive, which is why their
numbers have only decreased.
Activity Notes and Troubleshooting
• In order for students to extrapolate data with some accuracy, the scale for each graph
should be different. Students should make each graph fill the page. The greater the
scale is, the more detailed their graphs will be and the better their estimations will be.
Comparing the populations of different species in the same year is not meaningful in
this activity. Even a healthy ecosystem may be able to support different numbers of
each bird because of the birds’ needs.
• If you are evaluating this assignment, give feedback promptly so students can use the
feedback for Data Analysis Investigation 2-A, on page 79 of the student textbook,
which requires similar skills.
• If possible, arrange a field trip and have students participate in the bird counts in their
area.
Additional Support
• While some students may prefer to use a computer to graph the data, students are
usually better able to internalize the information and make better estimations when
graphing by hand. In the event that a student will not be successful unless he or she
uses a computer to plot the data, encourage the student to draw the best-fit line by
hand.
• If needed, students can practise drawing and interpreting line graphs using BLM G-25
Constructing a Line Graph and BLM G-26 Interpreting Line Graphs.
Answers
1. Overall, the downy woodpecker population is in equilibrium because the line of best
fit is almost horizontal.
Overall, the mourning dove population is increasing because the line of best fit is
sloped upward.
Overall, the ruffled grouse population is decreasing because the line of best fit is
sloped downward.

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 2. predators and lack of food
3. abundance of food and lack of predators
4. Yes. The lack of space may have contributed to the declining ruffled grouse
population. The mourning doves may be more comfortable in urban areas and find
food easier where people are around.
5. No. The ruffled grouse population would be negative in a few years if the population
continued along the line of best fit.

Learning Check Answers (Student textbook page 51)

1. Populations tend to increase when individuals reproduce at rates that are greater
than what is needed to replace individuals who have left the area or died.
2. There were no limiting factors such as predators. There was an abundance
of resources.
3. nutrients, space, light, predators, or dissolved oxygen (in aquatic ecosystems)
4. Answers will vary. Resources that quickly became limited were gasoline, other
fuels, water (if electrically pumped), some food (refrigerated), batteries, candles,
and so on.

Section 2.1 Review Answers (Student textbook page 55)

Please also see BLM 2–3 Section 2.1 Review (Alternative Format).
1. The population will be slowed or stopped by limiting factors. It cannot grow beyond
the carrying capacity.
2. The carrying capacity would decrease because flying squirrels depend on the holes
in dead trees for roosting.
3. The first female will produce 10 offspring and then each daughter as well as the
female herself will produce 10 in the second year. The population goes from 1, to 11
(10 + 1), to 121 (10 + 1 + 110).
4. Growth of shade-intolerant plants reduces space for the dace. The decline in the
numbers of dace’s prey due to change in habitat limits the growth of the dace.
5. The population undergoes exponential growth between 0 and 40 days, then begins
slowing down toward its carrying capacity. After 90 days, the population growth is
in equilibrium. Possible limiting factors for the population could include food and
space.
6. The objective stops all actions that would decrease the carrying capacity, such as
urban sprawl, and promotes action that would improve the supply of water, shelter,
and natural food in the area. These actions should maintain or increase the carrying
capacity of the area.
7. Intensification requires that a large percentage of new development occurs on land
within the built boundaries of a city.
8. a. Answers will vary depending on the community. Students may have examples of
urban sprawl, intensification, or construction designed to increase the carrying
capacity in an area.
b. Answers will vary depending on the community. Limiting factors may include
humans, predators, space, and access to resources.

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 Section 2.2 Interactions Among Species
(Student textbook pages 56 to 64)

Specific Expectations In this section, students will learn that each species occupies an ecological niche, which
• B2.1 use appropriate has biotic and abiotic components, and many species occupy a narrow niche for which
terminology related to they are highly adapted. Students will use the terms predation, competition, mutualism,
sustainable ecosystems, and parasitism to describe relationships between species. Students will explain how these
including, but not limited to:
relationships define a species’ niche and affect its distribution and abundance.
bioaccumulation, biosphere,
diversity, ecosystem, equilibrium,
sustainability, sustainable use,
Common Misconceptions
protection, and watershed • Students may believe that each species is ideally adapted to its one specific niche,
• B3.3 describe the limiting and that different species co-exist in an ecosystem because they get along. Niches
factors of ecosystems, and are not species-specific. Orcas in different pods will occupy different niches; some
explain how these factors affect pods hunt only fish, while others will hunt larger animals such as seals. Most species
the carrying capacity of an occupy a niche that is much narrower than what they are adapted to, most likely
ecosystem
because of competitive exclusion.
• Students may believe that predators only affect the population of their prey.
However, the predator and prey are part of a larger food web. For example, wolves prey
on deer; deer browse deciduous saplings; deciduous saplings compete with coniferous
saplings for light and nutrients. If wolves are removed from this food web the forest
cover eventually changes from mixed conifer deciduous to predominantly deciduous.
• Students may think that the higher a species is in a food chain, the larger the
species is. This belief implies that the more links there are in a food chain, the
larger a predator will be. A predator does not need to be larger than its prey. Wolves
outnumber their prey to overcome it, and a lone wolverine is capable of taking down a
moose. The largest predator on the planet is at the top of a very short food chain. Blue
Whales eat krill, and krill eat phytoplankton.
• Students may think that relationships that seem mutualistic are always mutualistic.
At some point you may have learned the saying, “Alice algae took a likin’ to Freddy
Fungus.” This pneumonic helped you remember that lichens were a result of a
mutualistic relationship between algae and fungi. The relationship is more parasitic
than mutualistic, however; the fungus seeks out the alga and traps it within its own
structure, and the alga is “forced” to work for the fungus.

Background Knowledge
No two species can occupy the same niche. One species will be forced to adapt its
requirements and move to an adjacent niche; in essence, one species will have to
settle for less. For example, nuthatches live in the same habitat as woodpeckers, and
the nuthatches will nest in abandoned woodpecker cavities. Both species eat small
insects and larvae; however, the nuthatch does not bore large holes into the tree as
the woodpecker does. Instead, the nuthatch moves down the tree, facing the opposite
direction, and pries out what other birds have missed. Competitive exclusion is the
process of one species pushing a competing species out of the environment to which
both are adapted.

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Literacy Support
Using the Text
Before Reading
• Have students scan the section and create a list in their notebook of Key Terms, as
well as other words that they find in headings or definitions, which seem important.
Tell them that as they read, they will be looking for relationships among these
ideas. Students can create these lists on their own or in pairs. Have students list
approximately 20 terms.
• Ask students to predict what they might learn about these terms as they read the
section.
• ELL English language learners can work with a fluent English speaker. Have them
also identify words that they do not understand, and use the glossary or ask their
partner for clarification.
During Reading
• Have students make notes or draw diagrams to show how groups of the words they
wrote are connected. For example, predation, competition, mutualism, and parasitism
all describe ways in which species interact. No two species can occupy the same
niche. If students have trouble identifying connections, brainstorm a few together as
examples.
After Reading
• Have students create a concept map. Students may want to attach two pieces of
notebook paper to make a larger piece of paper, or work in a group and use chart
paper, for this activity. It is useful to have some coloured pencils or markers on hand.
Students should include on their maps the terms they listed before reading. They can
then indicate how the terms are connected, on the lines that join them. Unlike a mind
map, each concept can have many connections, and the connecting phrases are as
important as the terms. See BLM G-34 Concept Map and BLM A-11 Concept Map
Checklist.
Using the Images
• For Figure 2.10, on page 57 of the student textbook, ask students to list the similarities
and differences between the sundew and pitcher plant in their notes. They can draw a
Venn diagram or use BLM G-39 Venn Diagram.
• For Figure 2.11, on page 58, ask students to verbally describe the trends in the graph.
Ask, “Why is the hare population usually higher than the lynx population?” “Is there
any time when it is not higher?” “Does the lynx population peak at the same time as
the hare population?”
• For Figure 2.12, on page 59, ask students how the wolf/moose graph differs from the
lynx/hare graph. Students may volunteer answers verbally, and you can record their
answers on the chalkboard for students to copy. Ask students why the wolf population
can exceed the moose population, when the lynx population does not usually exceed
the hare population.
• For Figure 2.13, on page 60, students should be able to identify a linear relationship,
and make the connection to carrying capacity. Ask students if the total number of
eggs laid for all female song sparrows increases or decreases as the number of females
increases.
• For Figure 2.16, on page 63, ask students to find and record the answers to the
following questions: How many hosts do the brainworms require; how many organs
do they infect; and which parts of their lifecycle take place in the deer? Students can
record on BLM 2-4 Brainworms and White-tailed Deer.

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 Assessment FOR Learning

Evidence of Student
Tool Supporting Learners
Understanding

Selected Students define and apply the To help students build an understanding of niche, brainstorm some
Response concept of an ecological niche. characteristics of the niches of familiar animals or plants, for example,
Learning Check squirrels, dandelions, or honeybees. Have students consider all of the
questions, organisms‘ needs when listing elements of their niche. Ask them how
page 61 the niche of one organism might be different from the niche of a similar
organism, for example, rats, clover, or wasps.

Section Review Students use examples to explain Divide the class into eight equal groups. Assign each group a question to
questions, how relationships with other species answer. Students in each group should discuss the answer until everyone
page 64 help to define a niche. in the group understands and agrees with it. Then they should record
their answer on chart paper or an overhead transparency. After 10 to
15 minutes, have each group quickly present their answer. All students
should copy the answers into their notebooks. Answers could be left on
display for students to copy at their own pace.

Performance Students are able to separate the Some students may be squeamish about using actual owl pellets.
Activity 2-3, smaller pieces from the owl pellet Owl pellets are the indigestible parts of the meal that the owl later
What Was for and use a key to identify them. regurgitates.
Dinner?, page 60 There are many online virtual versions of this activity, which students
can complete as an alternative activity or as preparation for this activity.
See www.scienceontario.ca.

Instructional Strategies
• DI In groups of three, students can do a predator-prey simulation using playing
cards and paper clips. See BLM 2-5 Predator-Prey Simulation. Students drop paper
clips and cards from a fixed height to simulate the predator-prey relationship. A card
landing on paper clips represents rabbits that have been consumed. Each group should
delineate a 50 cm by 50 cm area and drop three paper clips (rabbits) and one card
(lynx) from a height of 50 cm. Repeat the drops 25 times. Each drop represents a
generation of rabbits and lynx. Cards and paper clips that fall outside the 50 cm by 50
cm square have died. Students will record the number of surviving rabbits and lynx
after each generation. After 25 generations, each group can graph their results. This
activity should help spatial, bodily-kinesthetic, and logical-mathematical learners
understand the predator-prey relationship.
• Have students respond to the following statement by placing themselves along a
value line for the following statement: Competition between two species is always
beneficial to both species. After students have placed themselves along the line from
agree to disagree, divide the line in half. The two halves of the line will form an inside
circle and an outside circle. The agree side forms a tight circle facing outward, and the
disagree side forms a larger circle around the first one facing inward, so that students
are facing each other. Allow each side 20 seconds to argue their position. When the
inside and outside circles are finished, rotate one of the circles to the right by one or
two students. Continue in this manner until students in the rotating circle have moved
around the stationary circle once. Students can then write the statement in their
notebooks and draw a value line. They should place an A on the value line to represent
where they stood before the activity and a B on the value line to represent where they
stood after they had discussed the issue with classmates. They should also write a brief
explanation of how their opinion changed or why it did not change.
• Inquiry Investigation 2-B, on pages 80 and 81 of the student textbook, provides
students with an opportunity to carry out an experiment to determine the effect of a
limiting factor on the growth of a bacteria population.

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• DI For interpersonal and bodily-kinesthetic learners, arrange the class into groups
of four to six. Have each group create a brief role-play to demonstrate mutualism and
parasitism. Students could use situations from their own experience at school. For
example, a skit about a student who is always borrowing pens and paper, and who
never returns them, might illustrate parasitism.
• ELL English language learners may know of other animals that share interesting
predatory, parasitic, or mutualistic relationships. Invite them to tell the class about
these animals.

Activity 2–3 What Was for Dinner? (Student textbook page 60)
Pedagogical Purpose
This activity provides students with an opportunity to directly observe and investigate
evidence of a predator-prey relationship.

Planning

Materials Owl pellet

Paper towel
Forceps, tweezers, or probe
Magnifying glass
BLM G-40 Activity 2-3, What Was for Dinner? Identification Key

Time 30 min
10 min to view on-line simulation

Safety Ensure students wear safety goggles if they are using a squirt bottle with alcohol to disinfect.
Ensure students wear gloves. Students with allergies to latex should not wear latex gloves.
Emphasize hand washing and wiping down work surfaces afterward.
Tell students how and where to dispose of waste.
Some students with animal allergies or asthma may have reactions while doing this activity.

Background
Some students may be squeamish about this activity as they assume the pellets are
fecal matter. The pellets are the indigestible animal parts that are regurgitated by
the owl. There are on-line versions of this dissection readily available. See
www.scienceontario.ca.
Activity Notes and Troubleshooting
• Project an on-line simulation to introduce the procedure.
• It is best for students to work in pairs for this activity, so that students have
opportunities to closely examine the contents of the pellet.
• Form pairs by asking who would prefer to pull apart the pellet (dissector) and who
would not (recorder). Pair the dissectors with the recorders.
• Some students may want to record the dissection with their cellphone cameras. The
recordings could be uploaded to a class website.

Additional Support
• While the Internet is a great supplement to any dissection, it is not a substitute.
Encourage students to participate in the activity, and establish varied levels at which
they can participate. If students are absolutely unable to participate, ensure that they
have the opportunity to watch an Internet simulation.

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 Answers
1. An owl’s prey depends on the size of the owl. Smaller owls eat insects and spiders,
and larger owls will eat small animals including other birds. Owls are predators.
2. Answers may vary depending on the owl pellets. The prey is probably very abundant
in the owl’s ecosystem and easier to catch than other potential prey.
3. fish bones and cartilage

Learning Check Answers (Student textbook page 61)

1. An ecological niche is the way that an organism occupies a position in the
ecosystem, including all the necessary biotic and abiotic factors.
2. The moose population is influenced by exceptionally cold winters, tick infestations,
and predation by wolves. The wolf population is significantly influenced by the
number of moose.
3. The advantage would be that it is a simpler system so there are not so many other
factors that might be involved. The disadvantage is that the patterns might not apply
to natural situations where there are additional predators and herbivore prey.
4. On the single-bird island, you might expect the bird to feed in both pines and
maples, but on the two-bird island, because of competition, you might expect that
one species will forage in maples and the other will forage in pines.

Section 2.2 Review Answers (Student textbook page 64)

Please also see BLM 2–6 Section 2.2 Review (Alternative Format).
1. An ecological niche is like a job because organisms must go about the business of
surviving and reproducing and in doing so provide services to the ecosystem. It is
not like a job in the sense that organisms do not have obligations or responsibilities
to their ecosystems.
2. The niche would shrink over time.
3. The plants are carnivorous. They capture and consume insects. Bogs have relatively
acidic soil and water, and they are nutrient-poor environments.
4. Bats import nutrients into cave ecosystems through their droppings. Carnivorous
plants import nutrients into the bog by capturing and digesting insects.
5. You would have to consider what resources elk need and whether these resources are
available or not. You would have to consider the potential predators in the ecosystem
and what competition for food the elk may have. You would have to consider
whether the brainworm in white-tailed deer would affect the elk.
6. Since the plant food is never in short supply, the best explanation for the periodic
decline in hare numbers is that there are a lot of lynx at that point. This result would
suggest that it is top-down regulation. Top-down regulation means that the number
of predators affects the prey population. Bottom-up regulation means that the
amount of food, such as plants or animal prey, affects the population of the animals
that eat them.
7. By having the two sexes consume different kinds of prey, their offspring have access
to more resources. This result may increase the carrying capacity in a certain area.
Although they are not different species, this size difference might also reduce
competition between the two sexes.
8. The coral provides protection for the algae inside its tissues and coral skeleton,
and the algae photosynthesizes and provides food (energy) for the coral. Marine
algae can be colourful and when they die, their colour disappears along with them,
causing bleaching.

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Section 2.3 Human Niches and Population
(Student textbook pages 65 to 68)

In this section, students will learn how we have broadened our niche by altering the Specific Expectations
ecosystem that supports us. Even though our intellectual and technological abilities have • B3.3 describe the limiting
enabled us to alter our ecological niche, human societies are still subject to the principle factors of ecosystems, and
explain how these factors affect
of carrying capacity. Students will learn about doubling time and that the human
the carrying capacity of an
doubling time is now less than one lifetime. Students will calculate their own ecological ecosystem
footprint, and make suggestions to reduce their footprint.
• B3.5 identify various factors
related to human activity that
Common Misconceptions
have an impact on ecosystems,
• Students may believe that humans have adapted to nearly any environment on and explain how these factors
Earth due to humans’ intellect and technology. We have not physically adapted; affect the equilibrium and
instead, we alter our environment. survival of ecosystems

• Students may believe that we know how many humans Earth can support.
Estimates for the carrying capacity of Earth range from 1 billion to 15 billion. There
is currently no accurate estimate of what the current carrying capacity for humans
should be. The population of Earth at this time is over 6.5 billion.
• Students may believe that the rate of human population growth is increasing. In
fact, the rate of population growth has steadily decreased since the 1960s; however, it
is still above zero, so our population continues to grow.

Background Knowledge
The actual number of humans that Earth can support is a debated number that ranges
between 1 billion and 15 billion. Around 1 a.d., it is estimated that Earth’s population
was only a few hundred thousand people. Advances in agriculture, sanitation, and
medicine have extended our life spans, decreasing our death rate. The human genome
has not significantly changed in that time. Although there is anecdotal evidence of
ancient Patagonians who adapted to the cold and who could sleep in the snow, recent
research has shown that there may have been some genetic drift due to the isolation of
this population. This population is now all but extinct.
It is commonly felt that the lack of available fossil fuels will be the limiting factor
to human population growth. We should be more concerned about the availability of
fresh water and its ability to irrigate crops. Irrigation and its affect on soil salinity are
too often overlooked. We are dependent on irrigation to supply enough food to nourish
6.5 billion people; however, once soil has become infertile due to salinization, it cannot
be recovered. This information leads us to question whether or not our planet can
support the estimated 9 billion people who live on it.

Literacy Support
Using the Text
Before Reading
• ELL Preview the vocabulary with English language learners. Make a word web for
the term sustainable, since it comes up in many forms in this section. In English,
sustain can mean carry, bear, or maintain.
• Help students connect to prior knowledge. Present students with a statement such
as the following: We need to live in a more sustainable way without changing our
environment to increase its carrying capacity.
• In their notebooks, students will prepare a T-chart with one side for ideas that
support the statement, and the other side for ideas that oppose the statement. At the
bottom of the page, have students leave two spaces—one for Decision, and the other
for Reasons.

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 • After a brief class discussion, and after scanning the text, have students record one
idea for each column of their T-chart.
During Reading
• Students can read the text to themselves, or take turns reading as a class. On their
T-chart, have them summarize what they read by recording supporting and opposing
ideas in the appropriate columns.
• ELL To ensure English language learners understand what they read, have them use
sticky notes to indicate problematic words and phrases, and then discuss them as a
group.
After Reading
• Students can review the statement they were presented with before reading, and
decide which viewpoint they would take. Then they can record their decision in the
appropriate space on their T-chart.
• Students should discuss and share their decision with a classmate. Afterward, each
student will record the reasons for his or her decision in the appropriate space on
their T-chart.
Using the Images
• For Figure 2.17, on page 65 of the student textbook, ask students to explain the
physical advantages that the human brain and hand have over other animals, for the
niche we inhabit. Students may notice that the human brain occupies about 50 percent
of the scull, and has more surface area because it is wrinkled; and that the bones in the
human hand are separated into fingers much farther down the finger joints than in the
bear paw.
• Project the graph at the left of Figure 2.18, on page 66, for the class, or sketch it (with
labelled axes) on the chalkboard. Poll students as to when the industrial revolution
began based on what they see on the graph. As well, ask what might have happened
around 1400, and what major scientific advances were made between 1800 and 2000.
• For Figure 2.19, on page 67, ask students which two countries are below the global
average, why this might be, and whether they think these countries will stay this way.

Assessment FOR Learning

Tool Evidence of Student Understanding Supporting Learners

Selected Response Students describe reasons for, and effects of, In groups of four, have students respond to the questions
Learning Check rapid human population growth. on chart paper or mini white boards. Allot a few minutes for
questions, page 67 the groups to respond to the questions. Afterward, post the
questions around the classroom and have students conduct
a “gallery walk” to view all of the answers posted. After
viewing all the answers, discuss them as a class and have
students record the correct answers in their notebooks.

Selected Response Students describe how humans have Have students use a cause-and-effect map to record the
Section 2.3 Review increased their carrying capacity and list effects of increased intellectual abilities as they reread
questions, page 68 factors that contribute to our ecological page 66. Have them work in pairs and create a T-chart to
footprint. list sustainable activities and unsustainable activities. See
BLM G-33 Cause-and-Effect Map and BLM G-38 T-chart.

Data Analysis Students describe strategies to reduce their Have students list five things they have done today, and the
Investigation 2-C, ecological footprint. impacts on the environment of each one. They can use a
Putting Your Foot in cause-and-effect map to record these activities and impacts.
Your Mouth, page 82 Then ask students how they could change their activities to
reduce the impact on the environment.

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Instructional Strategies
• DI Have students do an Internet search and critique for this section. This activity
can be done in groups, pairs, or individually, and should appeal to linguistic, logical-
mathematical, and spatial learners. Assign students a category to research, such as
brain size and intelligence, human population growth, ecological footprint, or human
carrying capacity. Students should find three to four websites that are related to their
topic. They can then write a critique for each website, answering the following
questions:
• Is the Web page informative? What can you learn from it?
• Is the language clear and easy for a typical high school student to understand?
• Do the interactive illustrations and animations work, and do they add to your
understanding of the topic?
• How current is the information? What type of institution or organization is
responsible for providing the information?
Students can briefly share their findings with the class.
• As a class, create an action plan to reduce the class’s ecological footprint for one
month.
• Students must suggest ways that the class as a whole and each individual can reduce
the ecological footprint.
• Students must decide how they will monitor and encourage participation. They
must also determine how they will evaluate the success or failure of the plan. Then
have them carry out the plan.

Learning Check Answers (Student textbook page 31)

1. By building complex tools, controlling external forms of energy, and expanding
the use of resources, humans have been able to live successfully in many different
ecosystems.
2. Sustainable use is use that does not lead to long-term depletion of a resource or
affect the diversity of the ecosystem from which the resource is obtained.
3. The current doubling rate is about 60 years.
4. No one knows what the sustainable carrying capacity is for humans, but many
scientists believe that it is around 9 or 10 billion.

Section 2.3 Review Answers (Student textbook page 68)

Please see also BLM 2-7 Section 2.3 Review (Alternative Format).
1. We have been able to redefine and expand our niche, allowing us to go everywhere
on the globe. By learning to control energy and resources, we have increased the
biosphere’s carrying capacity for humans, at least for now.
2. Answers will vary. Students may describe street boundaries, neighbourhood, school,
and/or their home. Their niche may include places where they regularly shop, visit,
or play sports. A sketch would contain similar information. It would be interesting
to compare the different sizes and complexities that students come up with.
3. by increasing the availability of energy and resources for consumption, or by
reducing consumption
4. Humans made great advances in increasing carrying capacity by being able to
control fire; make clothes; make weapons; plant crops; domesticate animals; and
improve public health, education, agriculture, medicine, and technology.
5. Answers will vary; Possible answer: Toes: recycle, compost, ride a bicycle, am a
vegetarian, grow vegetables, take short showers; Heel: do not eat imported fruit and
vegetables; Middle: get a ride to school every day

978-0-07-072367-2 Chapter 2 Populations and Sustainable Ecosystems • MHR TR-1-53

 6. a.
National Footprints
14

(hectares per person)

Ecological Footprint
12
10
8
6
4
2
0

an

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ia

om

es
te
az

si
pa
op

at
ist

d
ira
Br

Ja

Ru
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St
an

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ab

d
Af

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Un
Ar

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ite
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Country

b. largest: United States and United Arab Emirates; smallest: Afghanistan and
Ethiopia
c. Differences occur due to the way resources are being used. There may be a
conscious effort to reduce the footprint through sustainable use of resources or
simply a lack of resource use, making a footprint low. For countries with large
footprints, resources are plentiful and may not be used in a sustainable manner.
7. The vast landscape of Canada and seemingly unlimited natural resources may have
encouraged us to be over-consumptive and wasteful. Canada also has a cold climate
for much of the year, which requires us to use more energy for heating than in
warmer countries.

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Section 2.4 Ecosystem Services (Student textbook pages 69 to 78)

In this section, students will learn that when a species occupies its niche, it is able Specific Expectations
to support or provide services for other organisms. Examples of ecosystem services • B3.1 compare and contrast biotic
provided by a species include the forests’ influence on climate and watersheds, and and abiotic characteristics of
insects’ ability to provide pollination and decomposition. Students will understand that sustainable and unsustainable
terrestrial and aquatic
the health of a population may depend on more than one ecosystem, as is the case with
ecosystems
migratory birds. Maintaining the health of the ecosystems required by migratory birds
• B3.5 identify various factors
requires international co-operation. Students will also be able to express how ecosystems
related to human activity that
have provided them with recreational benefits due to the beauty of the natural have an impact on ecosystems,
environment. and explain how these factors
affect the equilibrium and
Common Misconceptions survival of ecosystems
• Students may believe that ecosystem services are freely provided by nature.
However, we need to protect and preserve the environment necessary to maintain
these services. For example, we enjoy breathing oxygen, but we must ensure that we do
not damage the forests and aquatic ecosystems that, through photosynthesis, produce
oxygen.
• Students may believe that most of the ecosystem services do not directly impact
humans, and that they are just exchanges between other species of plants and
animals. The fresh water that most of the Greater Toronto Area (GTA) population
consumes comes from Lake Ontario, which is fed by several rivers whose headwaters
are located on the Oak Ridges Moraine. In order to continuously supply the rivers
and the lake with fresh water, the springs and headwaters need forest cover. This
requirement comes at a cost to GTA residents who want more housing each year that
is within commuting distance of the city.
• Students might think that mosquitoes and black flies do not provide any ecosystem
service at all, and that they are nuisances that humans and animals could do
without. Only female mosquitoes consume blood; the males consume nectar and are
pollinators for many plants. Mosquitoes are also the main food for many bird and fish
species, and black flies pollinate wild blueberries.
• Students might have heard that domesticated cats are to blame for the migratory
songbird decline. While cats do prey on birds, they more often hunt and catch small
rodents and amphibians. The leading cause of songbird decline is more likely due to
habitat degradation both in the boreal forest and tropical forest.
• Rivers and streams that drain a watershed are commonly protected with a narrow
band of trees and vegetation, and students might think that this band of trees
and vegetation will protect water quality and prevent erosion. While these buffers
do provide some protection and are necessary, the importance of protecting the
headwaters of the river cannot be overlooked. Without forest cover, the headwaters
will dry up. Deeply rooted trees help water to percolate down to the aquifer, and they
act as a sponge, often helping to hold groundwater for decades. Building communities
with low densities and surrounding golf courses adds to the problem because mowed
lawns result in almost the same amount of run-off as a paved parking lot.
• Students might think that by designating an area as protected, we can preserve
tracts of natural areas and exclude them from human recreation. Unfortunately,
designating an area as protected does not preserve it. People will continue to use it for
a variety of purposes if it makes their lives more convenient or enjoyable. This result is
due to our anthropocentric (human-centred) way of thinking. It is also true that areas
depend on one another. If protected areas are separated by roads or communities, they
may deteriorate.

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 Background Knowledge
Songbirds are keystone species that are indicators of environmental health, particularly
forest health. We often think about the forest as a faraway place that provides us with
products such as wood and paper, but we forget to think of the forests that surround
and intersect our cities and communities. As our communities intersect the natural
community more, other wildlife species are impacted as well.
One of the most important benefits provided to us by a healthy forest, including the
urban and suburban forest, is clean drinking water. Forests and natural environments
prevent rain and meltwater from running off, washing away nutrients and soil. The deep
roots of trees provide the best retention of water, sometimes for decades. Agricultural
land provides less retention than forest, and mowed grass provides as little water
retention as a paved parking lot. It is important to maintain large, continuous tracts of
forest around headwaters of major streams and rivers.
As well as protecting fresh water, forests can provide corridors to link isolated
ecosystems and communities. One such example is the Yellowstone-to-Yukon
corridor, proposed to protect the genetic diversity of the often-too-isolated grizzly bear
population.

Literacy Support
Using the Text
Before Reading
• To help students make connections between the text and their own experiences
and opinions, provide them with a template of a T-chart with a summary box at the
bottom. Title the left side of the chart, “I Read,” the right side of the chart, “I Think,”
and the bottom “Therefore.”
• Using a projector, model how to use the chart for the first few paragraphs of text.
In the “I Read” column, write a couple of points to summarize a subsection of text.
In the “I Think” column, write an opinion or a question that a reader may have in
response to the points in the left column.
During Reading
• Individually, have students fill out their own T-charts. They can read silently or use a
read-aloud strategy, such as reading tag or reading in pairs. Tell them to write at least
one point in the left column for the text under each heading in the section. Then have
them fill in the second column for each point in the first column.
After Reading
• Students can reread their own T-charts and identify similarities and differences
between the two columns. They may want to use highlighters to compare the two
columns.
• Students can then write a concluding or summary statement in the “Therefore” box
at the bottom of the page. Students can share their concluding statements with their
group or the class.
• Students can summarize what they have learned about ecosystem services using
BLM 2-8 Ecosystem Services or BLM 2-9 Ecosystem Services (Alternative Version).
Using the Images
• In Figure 2.21, on page 70, students are provided with another opportunity to
interpret a graph. Invite students to share one thing they can learn from this graph,
until most of the information has been conveyed. Ask students why the run-off did
not start as soon as the cutting was finished. (The cutting finished in mid-winter, and
the run-off started with the spring thaw.)

TR-1-56 MHR • Unit 1 Sustainable Ecosystems 978-0-07-072367-2

• For Figure 2.24, on page 73, ask students what the significance is of the name of the
beetle. Ask why the beetles bury their finds and what we can tell about the beetle’s
niche from this diagram.
• For Figure 2.25, on page 74, you may need to provide some more information
about the four bird species, either from the Internet or a field guide. Ask students to
speculate why there might be such a sharp decline in the bank swallow population
compared to the common nighthawk. The answer could be related to their nesting
preferences, and the impact that habitat destruction has had on these species. Bank
swallows dig out hollows in the sides of river banks, while nighthawks roost high in
trees.
• For Figure 2.26, on page 75, ask students to describe the diversity of the plants shown
in each photograph. Ask students to look only at the photographs (and to not read the
text above), and ask them which situation looks to be better for mass production, and
why.
• For Figure 2.27, on page 76, ask students if the girl is snowshoeing in a natural area,
park, ski resort, or farm, and why they think that.

Assessment FOR Learning

Tool Evidence of Student Understanding Supporting Learners

Selected Response Students describe examples of ecosystem Have students work in pairs on just one of the three main
Learning Check, services and explain the effects on the topics of the section—forests, insects, or birds. Have pairs
pages 71 and 74 ecosystem if these services were removed. create a main idea web to show the ecosystem services that
Section 2.4 Review each organism provides. How many ideas can they include?
questions, page 78 Students who have created different webs can share their
results.

Performance Students describe the importance of the Pre-select several websites to direct students to.
Activity 2-4, monarch’s winter ecosystem and the threats Check that students have answered all of the questions
Ecotourism and to it. Students create a pamphlet that before starting the pamphlet.
Monarch Butterflies, promotes sustainable ecotourism to this Students may want to use publishing software for this
page 76 region. assignment.
For students who have difficulty organizing information
on their pamphlet, you can specify what to include in each
section.

Instructional Strategies
• For this section, it may be helpful to have a class set of field guides for the birds of
Ontario. If the school does not have any field guides, the school board’s outdoor
education centre may be willing to lend some.
• DI Plan a watershed top-to-bottom field trip. Choose a local stream or river and
plan a field trip that makes several stops along its course, from headwaters to the
mouth. Students can make observations of water quality and of the surrounding
ecosystem, and take measurements and water samples if possible. This field trip should
appeal to the bodily-kinesthetic learners as well as naturalistic and logical-
mathematical learners (if data are collected).
• Plan a field trip to a museum where students can see displays of local insects and/
or birds. Alternately, plan a visit to a conservation/outdoor education area that has a
program about songbirds or insects.
• Have students research a local park or conservation area and ask them to compare and
contrast the uses or purpose of the park. Ask, “Is it primarily used for recreation or
environmental conservation?”

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 • Students can create a landscape design for songbirds in a portion of the schoolyard
or in their own yard at home. The design should be accompanied by a plant list,
including whether the plant provides food or shelter, and in which season the plant
is grown.
• Making a Difference, on page 77 of the student textbook, encourages students to think
about ways to share what they know about wildlife with others.

Activity 2-4 Ecotourism and Monarch Butterflies

(Student textbook page 76)

Pedagogical Purpose
This activity provides students with the opportunity to consider the ecological
connectivity between two countries, and how ecotourism allows a region to protect an
ecosystem that otherwise might be put to less sustainable use.

Planning

Materials Book a computer lab where students have access to a publishing program and the Internet.
Obtain a few relevant resources from the library, such as books and magazines with information about monarch
butterflies and ecotourism.

Time 40 min, plus possible time at home to complete the pamphlet

Background
Monarch butterflies that breed early in the summer do not migrate, as they die shortly
afterward. Those that do not breed migrate to Mexico and live for another year. The
journey from Canada to Mexico is around 3000 km. Monarchs also overwinter in
California and Cuba. Canada provided technical assistance to Mexico to assist in the
development of a strategic plan for ecotourism in the monarch’s wintering area.
Activity Notes and Troubleshooting
• List a few websites for students to start their research with. Assist students
with search-engine queries, and in evaluating the results of those queries.
See www.scienceontario.ca.
• Students could use publishing software to design their pamphlet, or they could use
paper and coloured markers or coloured pencils.
• Provide some alternative resources, such as books and magazines.
• Check that students have answered all of the questions before they create a brochure.
Additional Support
• DI Order butterfly chrysalis kits and watch them develop in the classroom. Then
release the butterflies in the schoolyard. Students can observe and record the
development of the chrysalises. This activity will appeal to the bodily-kinesthetic and
naturalistic learners.
• DI Spatial learners may prefer to create a poster project on the life cycle of
monarch butterflies, including models of each stage.
• ELL Pre-selecting websites will assist English language learners focus their research
on appropriate Internet sites.
• ELL English language learners could create their pamphlet in their first language,
and explain it to you.

TR-1-58 MHR • Unit 1 Sustainable Ecosystems 978-0-07-072367-2

Answers
Procedure
a. Answers may vary. One sanctuary receives approximately 200 000 visitors between
November and March each year.
b. Mexico has developed a strategic plan for ecotourism and set aside 780 000 hectares
of forest.
c. Illegal logging will decrease the amount of habitat available for the butterflies, and
decrease the opportunities for tourists to view the butterflies in a scenic, pristine
environment.
Questions
1. Butterflies are important pollinators in Canadian ecosystems.
2. Answers will vary but may include the ideas that increased pollution (from car
exhaust) could affect the butterflies, increased car traffic could reduce the butterfly
population (if they are hit and killed by cars), or that the butterflies may be stressed
by the increased human presence in the forest.
3. Student’s pamphlets should include information about the region, about the
butterflies’ migration and life cycle, and about tourist practices that support the
fragile ecosystem.

Learning Check Answers (Student textbook page 71)

1. Ecosystem services are the benefits experienced by organisms, including humans,
which are provided by sustainable ecosystems.
2. Trees extract huge amounts of water from the soil. On hot days, much of this water
escapes through the stomata, adding water vapour to the atmosphere. This process
helps to reduce temperatures and form rain clouds. More than half of the moisture
above tropical forests comes from the trees.
3. severe droughts and erosion
4. The concentration of nitrates in run-off can increase from less than 1 mg/L to
around 40 mg/L.

Learning Check Answers (Student textbook page 74)

5. pollination and decomposition
6. negative effects of pesticides, interference from cellphone radiation, parasites,
negative effects of relocation
7. regulating the numbers of insects
8. a steady decrease in the numbers of all four species of birds over time

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 Section 2.4 Review Answers (Student textbook page 78)
Please see also BLM 2-10 Section 2.4 Review (Alternative Format).
1. maintaining the economic activities of some communities, influencing climate,
reducing erosion, and providing habitat for thousands of species
2. Desertification is the change of non-desert land into desert through processes
such as climate change and unsustainable farming or water use. It was important
to designate 2006 as the International Year of Deserts and Desertification to draw
attention to this problem worldwide. Raising the profile of the issue could result in
funds being directed to this problem or to international co-operation to reduce it.
3. Pollination is the process of getting pollen from the male part of a flower to
the female ovary of a flower. Butterflies, bees, and birds are good examples of
pollinators.
4. Colony collapse disorder is the widespread loss of honeybees from hives. Possible
causes are an Asian mite, a South African beetle, insecticides, and even radiation
from cellphones and cellphone towers.
5. The decline in their population is complicated to figure out because it is difficult to
determine where the problems may be. In Canada, where the birds live during the
summer, the cutting of trees could be affecting the population by removing habitat.
In tropical regions, where the birds live during the winter, the population could be
affected by insecticide use, as well as the cutting of trees to grow coffee.
6. In the deforested area, the concentration of nitrates in run-off increased from less
than 1 mg/L to around 40 mg/L. Without trees keeping water in watersheds, the
nutrients in the water are lost.
7. Governments should support plans that recognize the concept of connectivity. It
makes sense that countries that share ecosystems should have arrangements to
protect shared species within those ecosystems—not just next-door neighbours like
Canada and the United States, but countries far away with whom we share migrating
species.
8. The Haida people constructed tall totem poles that expressed their reverence for the
things depicted in these cultural features. The totem poles were artistic and showed
the respect the people had for the ecosystems they lived in.

TR-1-60 MHR • Unit 1 Sustainable Ecosystems 978-0-07-072367-2

Data Analysis Investigation 2-A Is the Winter Skate
Endangered in Nova Scotia? (Student textbook page 79)

Pedagogical Purpose
Students will be able to analyze and evaluate the effect of commercial fishing on the
winter skate population in Nova Scotia. Students will interpret the data provided and
decide whether the winter skate population should be considered at risk.

Planning

Materials Graph paper

Computer lab (optional)
BLM 2-11 Data Analysis Investigation 2-A, Is the Winter Skate Endangered in Nova Scotia? (optional)

Time 50 min

Background
Skates are species of rays, and their wings are edible. At one time, they were used
primarily as fish meal or pet food, and sometimes to produce imitation scallops. As the
cod fishery declined, the popularity of alternative fish increased. Skate are caught on
longlines, gill nets, and trawls.

Activity Notes and Troubleshooting

• Using a projector or printed pictures, show students what the winter skate looks like,
and identify its body parts. In particular, show students the “wings,” as those are the
edible parts of the fish.
• Students may need assistance with understanding the groundfish industry. Groundfish
live near or on the bottom of a body of water. Common species include cod, halibut,
and sole. You may want to provide pictures of these fish as well.
• Show a few examples of scatter plots and model drawing a line of best fit on the
chalkboard. Remind students of the graphs they drew in Activity 2-2, on page 52 of
the student textbook. When drawing a line of best fit, there should usually be an equal
number of data points on either side of the line.
• Students may need assistance selecting the values and scale for the x- and y-axes.

Additional Support
• If necessary, refer students to Math Skills Toolkit 3, Organizing and Communicating
Scientific Results with Graphs, on pages 557 to 559 in the student textbook.
• Students may prefer to complete this assignment on the computer. Direct students to
print off the scatter plot but to draw the line of best fit by hand.
• ELL Ensure English language learners understand what the Species at Risk Act is,
and that an act is similar to a set of laws.
• Pair students who have strong graphing skills with those who need support.

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 Answers
Analyze and Interpret
1. The line will generally be placed so that one end is at the 1971 point and the other
end is at the 2004 point.
2. The values do not decrease every year, but generally decrease from 1973 to 2004.

Conclude and Communicate

3. There is more than one justifiable guess because most points do not fall on the line
of best fit. But if you extrapolate, the biomass will be zero in about 2007, meaning
that in the annual samples, none will be caught.
4. Answers will vary, but presumably the trend is enough to have students think it
should be listed.
5. Students will have to weigh the benefit of protecting a species in trouble against
the economic cost of restricting an economically important commercial fishery.
Considerations might be impacts on fishery-supported households, fishery-
supported communities, cultural traditions, Aboriginal fishing, and government
costs in enforcing protection.
Extend Your Inquiry and Research Skills
6. a. In 1992, at the Earth Summit in Brazil, the Convention of Biological Diversity
was established to promote sustainable development. As part of Canada’s
promise to fulfill this convention, the Species at Risk Act became law in late
2002.
b. Evaluations will vary; however, it has been less than a decade since the Species
at Risk Act was proclaimed, and that may not be enough time to assess its
effectiveness. Visit www.scienceontario.ca to find more information about this
issue.

TR-1-62 MHR • Unit 1 Sustainable Ecosystems 978-0-07-072367-2

Inquiry Investigation 2-B What Happens When Food
Is Limited? (Student textbook pages 80 and 81)

Pedagogical Purpose
Students will conduct an investigation to determine the impact on a population when
the resources are limited.

Planning

Materials 2 plastic cups with labels

Felt marker
50 mL graduated cylinder
20 mL paramecium culture
Medicine dropper
1 drop yeast culture
1 toothpick
2 mL methyl cellulose
6 microscope slides
Scissors
30 cm cotton thread
Tweezers
6 cover slips
Light microscope
Plastic wrap
2 rubber bands
50 mL distilled water
BLM 2-13 Inquiry Investigation 2-B, What Happens When Food Is Limited? (optional)
BLM G-23 Data Table (optional)
BLM A-15 Data Table Checklist (optional)
BLM G-20 Parts of a Microscope (optional)

Time 40 to 70 min (initial set-up)

3 weeks to run

Safety Remind students to use care with the electric cord of the microscope.
Ensure students wear proper safety clothing, including gloves and lab aprons.
Have students clean up any water spills immediately.
Students should never direct the mirror of a microscope toward the Sun.

Background
This is a very simple model of how population size is related to the availability of food. It
is easy to conduct and easy for students to interpret the results.

Activity Notes and Troubleshooting

• Before commencing the experiment, ensure students have created their data tables.
Give them copies of BLM A-15 Data Table Checklist to help guide them.
• Model the set-up first, which will provide a backup set of paramecia, in case one is
needed.
• Some colonies will die; be prepared to collapse groups if this happens.
• When counting organisms under a microscope, it is a lot easier to keep a tabulation
either with tick marks on a piece of paper or with a hand clicker. If students try to
count in their heads, it is very easy to lose count.

Additional Support
• Show students a prepared slide of a paramecium so that they know what they are
looking for.

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 • If students have trouble organizing an effective data table, refer them to Science Skills
Toolkit 7, on page 545 of the student textbook.
• If students have never used a microscope before, they will need to practise making
slides and focussing first. Banana cells are easy to view; just dab a piece of banana on a
slide, stain it with iodine, and apply a cover slip. Using a microscope to view a banana
cell will allow students an opportunity to practise before they move on to viewing live
organisms. Students can refer to Science Toolkit 8, on pages 546 and 547 of the student
textbook, to review the proper procedure for using a microscope. See also BLM G-20
Parts of a Microscope.

Answers
Analyze and Interpret
1. Possible answer: By taking the average of the three, I get a better sense of how many
paramecia there are.
2. Food slows population growth a lot.

Conclude and Communicate

3. Predictions will vary. Some students may predict that the population may double
because the food supply has doubled. Others may predict that the growth is at its
maximum because the food supply is plentiful.
4. Determine how many drops are in the paramecium culture, and multiply the sample
size by that amount.
Extend Your Inquiry and Research Skills
5. a. Paramecium aurelia: 800 paramecia/mL
Paramecium caudatum: 200 paramecia/mL
b. The carrying capacity for Paramecium aurelia decreases to about
600 paramecia/mL and the population of Paramecium caudatum drops to zero.
c. Paramecium aurelia competes better and wipes out the population of
Paramecium caudatum.

TR-1-64 MHR • Unit 1 Sustainable Ecosystems 978-0-07-072367-2

Data Analysis Investigation 2-C Putting Your Foot in Your
Mouth (Student textbook page 82)

Pedagogical Purpose
Students will analyze how human activities and choices have impacted the carrying
capacity of Earth. An ecological footprint is a measure of demand on Earth’s resources.

Planning

Materials BLM 2-13 Data Analysis Investigation 2-C, Putting Your Foot in Your Mouth (optional)

Time 30 min

Background
There are many different tools and tables for calculating ecological footprints; each will
provide a different answer. The important message is that our North American lifestyle
is not sustainable for the entire population of the world, and sometimes it is the many
small choices we make that can have the greatest impact.

Activity Notes and Troubleshooting

• Refer students to the Science Skills Toolkit 1, Analyzing Issues—Science, Technology,
Society, and the Environment, on page 529 of the student textbook.
• Many students will have difficulty estimating some of the items on the table. They
might have the most difficulty with imported food (especially if they do not participate
in grocery shopping). Discuss examples of imported food (fresh fruit and vegetables in
the winter, tropical fruit, rice, and so on).
• Students often have trouble estimating distances travelled and car efficiency. Help
students make reasonable estimates.
• Stress that the accuracy of students’ estimates is not as important as how they plan to
reduce their footprint.

Additional Support
• There are many on-line versions of this activity available, which students may be more
comfortable with. See www.scienceontario.ca.
• Assign this activity for students to complete at home with their family members.
• Enrichment—This activity could be tied in with an energy-conservation Family
Action Plan for the entire electricity unit.
• Once students have come up with suggestions to reduce their footprint and
reduce their electricity use, have students ask their family members to implement
the suggestions for a month. Record the electric meter readings each week and
determine if the family has reduced the household footprint.
• ELL Explain the meaning of the idiomatic expression ecological footprint, and of the
investigation title “Putting Your Foot in Your Mouth.”

Answers
Analyze and Interpret
1. Answers will vary. Many students will be surprised by how much eating meat
contributes to their footprint.
Conclude and Communicate
2. Reduce the amount of meat eaten, and travel less by car and plane.

Extend Your Inquiry and Research Skills

3. Answers will vary.

978-0-07-072367-2 Chapter 2 Populations and Sustainable Ecosystems • MHR TR-1-65

Chapter Review Answers (Student textbook pages 84 and 85)
Please see also BLM 2-14 Chapter 2 Review (Alternative Format).

Make Your Own Summary

populations

grow each species

limited by occupies

at an
exponential rate an ecological
niche
carrying capacity

for animals
for humans defined by providing in humans

can be reduced
high but still
by human
exists—could be inter-species ecological broadened by
alterations (for
reached in a relationships services technology
example, urban
few decades
sprawl)

because of including for example

rapid acceleration predation, watershed and

pollination and
of human growth competition, climate
decomposition
and short mutualism, influence by
by insects
doubling time parasitism forest

Reviewing Key Terms 12. The doubling time now is about 60 years; the population
1. e. mutualism growth is not as fast now as it was then.
2. g. population 13. The population grows about 300 000 per day. So, it would
3. d. ecological niche take about 110 days to increase to 33 million people and
4. a. carrying capacity between three and four more days to increase another
5. f. parasite million people.
6. c. ecological footprint 14. When large forested areas are cleared, the local annual
7. b. connectivity precipitation drops and the climate gets hotter and drier.
Clear-cut forestry can also dry out soil and increase
Knowledge and Understanding erosion where soil is lost.
8. a. pack ice for feeding from
15. They help control the population of the insects they eat.
b. caves
Thinking and Investigating
c. material for building nests
16. Starlings are also cavity nesters and they compete with
9. hunting and the removal of forest native birds like the eastern bluebird for limited nest
10. Intensification is one way to reduce the impact of rapid sites.
population growth, so that the density of urban areas 17. You could collect the same kind of data from a different
increases and the outer edge does not have to grow. area that has not experienced such tremendous
11. The algae leave the coral, possibly in response to population growth. You could research the types of nests
increased water temperatures. The mutualistic and locations that these birds prefer and how urban
relationship between the coral and the algae breaks down sprawl affects them. You could research the change in
and the coral bleach and die. food availability for the bird species.

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18. Wind-pollinated flowers do not need to attract insects or 27. Answers will vary. Humans have been able to expand
other animals by being bright, large, and fragrant, so they their carrying capacity through technology. There are
are likely to be dull, smaller, and non-fragrant. other animals who will have population growth that is
19. a. The more seeds planted per square metre, the fewer beyond their carrying capacity (as in the predator-prey
seeds produced by individual plants. relationships in Figure 2.11, on page 58, and Figure 2.12,
on page 59) and who will then experience a sudden drop
b. There is increased competition among individual
in population.
plants, so each plant has less energy to dedicate to
seed-production. 28. It would mean a greatly increasing population (a
population boom) because not so many people are dying
20. A straight line would be unreasonable and contrary to
but the birth rate is remaining high.
the idea of carrying capacity. It is likely that the pattern
would be more like that shown in Figure 2.5 for the fur 29. The presence of the trees provides shade and reduces
seal, on page 51 of the student textbook. erosion so that water is retained longer in the soil.

Communication 30. This species is migratory and so it may not be

21. Answers will vary. Problems may include pollution and experiencing any difficulties in Canada but it may be
competition among people and nations for space for finding circumstances difficult in its wintering grounds
homes, access to fresh water, land for crops and livestock, or along the way there.
food supply, electricity needs, and so on.
22. Answers will vary. Students will need to balance what
is ecologically responsible with what is economically
possible.
23. Answers will vary. Activities could include things like
canopy-walking, white-water rafting, swimming with the
dolphins, zip-lining in the forest, whale watching, hiking,
scuba diving, and so on. Students may recount some
interesting stories.
24. An animal that is hunted by humans may not reach
carrying capacity because numbers are harvested
each year, preventing the population from reaching
the maximum. It is probably not a problem for the
ecosystem, but arguments could be made both ways.
Hunting might reduce numbers that could be used to
feed natural predators. On the other hand, hunting might
prevent some wild turkeys from starving if the carrying
capacity is reached.
25. Answers will vary. Plants and algae photosynthesize;
feathers can be used for nests of various animals; insects
aid in decomposition; decomposing plants and animals
contribute nutrients; woodpeckers provide access to trees
for insects, and so on.
Application
26. The redside dace populations are restricted to upper
reaches of streams because of unsustainable conditions
downstream. These conditions mean that the populations
are isolated and cannot move from one stream to
another.

978-0-07-072367-2 Chapter 2 Populations and Sustainable Ecosystems • MHR TR-1-67

 Chapter 3 Biodiversity

Materials In this chapter, students will discover that Earth’s biodiversity includes millions
Please see the teaching notes of species. They will learn that ecosystems are dynamic, particularly in terms of
for each activity for a list of the maintaining ecological balance and the impact of human activity on that balance.
materials required. Please see Students will be able to explain the role of certain species within a community or
page TR-35 for a summary of the
ecosystem. They will also be able to explain how human activities can affect biodiversity.
materials required in this chapter
and other chapters.
Using the Chapter Opener (Student textbook pages 86 and 87)
Advance Preparation • The protection of Alfred Bog, just east of Ottawa, was a publicly driven project.
• Begin assembling groups of small Poll the class and ask if students are aware of any similar projects in their area (not
items for the model ecosystems necessarily wetland-related), and whether students have been involved in these
in Activity 3-2, on page 93.
projects. For example, some students may have planted trees or built bird boxes with
• Students can review the Key scouts, or been involved with the yellow fish program.
Terms in Chapter 3 by using
BLM 3-1 Chapter 3 Key Terms. • Research the local wetlands in your area, and find out if any provide interpretive
programs. Plan a field trip or encourage students to visit one of the wetland areas.
Wetlands are excellent places to view birds and wildlife—students will have more
wildlife sightings in a wetland than in a forest.
• Have students learn the word origins for biodiversity and ecology. Bio means life;
therefore, biodiversity means the diversity of life. Eco is from the word for house,
and logy means the study of.
• Another example of publicly driven wetland protection is Oshawa’s Second Marsh.
This is the largest wetland in the Greater Toronto Area and is an example of how a
coastal wetland functions, as it is on the shore of Lake Ontario. Second Marsh itself
is 123 ha in area and is flanked by Darlington Provincial Park and McLaughlin Bay
Wildlife Reserve, bringing the total area of protected wetland up to 400 ha. This
type of wetland provides natural floodwater protection, filters contaminants from
the water, provides habitat for birds and wildlife, and provides spawning beds for
fish. In the 1970s and 1980s, the special interest group Friends of Second Marsh was
responsible for saving the marsh from development. In the 1990s, Friends of Second
Marsh participated in restoration projects. By 2000, Environment Canada and the
Canadian Wildlife Service granted the Friends group the responsibility of developing
educational and stewardship programs. Second Marsh is a sharp contrast to what
most urban shorelines look like, and sets an example for what they could become.

Activity 3-1 Biodiversity in Canada (Student textbook page 87)

Pedagogical Purpose
This activity will emphasize the importance of models in representing an idea or a
concept. Students may only associate the term model with something like a model
airplane. Students will learn that models can be two-dimensional, three-dimensional, or
simply a thought or an idea. This activity will also make students aware of the amount of
diversity that exists in some groups of organisms.

Planning

Materials Markers
Chart paper
Construction paper (optional)
Computer lab
Modelling clay, or other materials for constructing 3-D models

Time 30 min

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Background
As informed citizens, we can influence and have an impact on how our natural resources
and ecosystems are utilized. These efforts may take decades, but the impact will be much
longer lasting. Education is often the first step of an effective strategy.
Activity Notes and Troubleshooting
• This task has the potential to run overly long, but its function is really just to introduce
the central concept of the chapter, so limit the time you spend on it.
• Be very clear about what is acceptable as a model. Depending on your students, you
might tell them to construct, an appropriate type of graph, and graph the data. This
activity would be less time consuming in a computer lab, where students could then
select different charts and decide for themselves which would be most appropriate.
• As students evaluate their own and others’ models, have them consider how effectively
the model communicates the key ideas about biodiversity.
Additional Support
• Depending on students’ skills and learning styles, you may want to direct students
specifically to create a graph of the data using a computer.
• DI Bodily-kinesthetic learners could create physical models using either
modelling clay or paper and scissors. For example, students could make a cutout of
each organism and use the size of the cutout to represent the number of known
species. This way, the largest cutout would be an insect and the smallest cutouts would
be amphibians or reptiles.

Study Toolkit

Strategy Page Reference Additional Support

Identifying the Main page 93 Students can use sticky notes and the strategy described
Idea and Details page 105 in Study Toolkit 2, Reading Effectively: Monitoring
Comprehension, on page 564 of the student textbook.
If this is the first time they are using this strategy, you
might want to model the process for them.
English language learners may benefit from planning
their summary on BLM G-31 Summarizing.

Word Origins page 112 (restoration, reforestation) The meanings of common prefixes and suffixes are given
page 115 (bioremediation, bioaugmentation) in Study Toolkit 3, Word Study: Common Base Words,
Prefixes, and Suffixes in Science, on page 565 of the
student textbook.
English language learners can benefit from listing
other words that include the same prefix, for example,
biologist, and biodiversity.

Interpreting Tables page 90 Have students practise in pairs using any table. One
Activity 3-3, page 104 student identifies a cell by stating the row and column
headings, and the other student reads the information
found in the cell.
Also, ask questions about the tables in the textbook,
such as, “What trend to you see?”, “How many years are
shown?”, and “What unit is the zebra mussel population
measured in?”

978-0-07-072367-2 Chapter 3 Biodiversity • MHR TR-1-69

 Section 3.1 Measuring Biodversity (Student textbook pages 89 to 94)

Specific Expectations In this section, students will explain how biodiversity is calculated, and understand that
• B2.1 use appropriate it represents the variety of organisms found within a specific region. Students will learn
terminology related to that there are places on Earth with exceptionally large numbers of species in a small area,
sustainable ecosystems, and that some of these areas are so significant that they are labelled as hotspots.
including, but not limited to:
bioaccumulation, biosphere,
Common Misconceptions
diversity, ecosystem, equilibrium,
sustainability, sustainable use, • Students may think that large, empty spaces, such as vacant lots and hydro
protection, and watershed corridors, do not contain any biodiversity. This belief is often used as the reason to
keep these areas mowed and “under control.” However, these areas provide habitat for
small animals and birds, which are food for hawks. The wildflowers also provide food
and a habitat for insects and butterflies. In most cases, hydro corridors can be excellent
places to encourage the growth of wild berries. Only the trees need to be managed to
prevent damage to the power lines.
• Students may feel that biodiversity is only relevant to wildlife and their habitats,
and has no direct impact on humans other than to provide us with the reassurance
that animals have been saved and protected. Biodiversity gives an ecosystem the
flexibility and genetic resources to adapt to environmental changes. Biodiversity also
applies to agricultural practices. We have bred out the diversity in most of our food in
favour of monocultures. In order for crops to adapt to disease or pests, scientists often
have to reach back to ancient crop species to introduce a greater diversity of genetic
material.
• Students may be concerned about protecting some species (for example, polar
bears) but not others (for example, lichen). In the past, conservation ecologists
often chose a “poster” species to evoke emotional reactions and encourage support
in protecting that species’ environment. Not all poster species are keystone species:
otters fulfill both categories but wolves, while handsome, are not keystone species. If
we manage to meet wolves’ needs for habitat and prey, we do not necessarily take into
account the needs of more sensitive species, such as pine marten or lynx; however, the
public has a more emotional attachment to wolves than to pine marten.

Background Knowledge
The term biodiversity comes from the concept of biological diversity. Biodiversity refers
not only to the number of species in a given area, but the genetic diversity of those
species as well. It is difficult to apply a numerical value to biodiversity because its nature
varies from ecosystem to ecosystem. We cannot compare the diversity of the Canadian
Arctic to the Amazon rainforest. A biodiversity index, as in Activity 3-2
(on page 93), is one way of quantifying the diversity of species in an area.
Biodiversity hotspots refer to areas that have a significantly larger number of species
in comparison with the surrounding areas. Hotspots in Ontario include the Carolinian
forest, which has endangered orchids, snakes and fish, and a large number of unique
tree species. Other Ontario hotspots include the Algoma Highlands, home to old growth
maple and birch trees, and a habitat for wolves, lynx, and bald eagles. The Great Lakes
can be considered hotspots because they contain one fifth of the world’s fresh water.
The short and tall prairie grasslands in Manitoba, Saskatchewan, and Alberta—once
home to the extirpated plains grizzly and black-footed ferret, and the endangered swift
fox, is another Canadian hotspot. (Extirpated species are locally extinct but still exist
elsewhere.)

TR-1-70 MHR • Unit 1 Sustainable Ecosystems 978-0-07-072367-2

Literacy Support
Using the Text
Before Reading
• Have students preview the text features. Students can create a three-column table
in their notebooks. The first column is for terms, the second is for definitions and
explanations, and the third is for pictures. The students can then scan the text for Key
Terms and headings (there are three Key Terms and five headings) and copy them
into the first column. The table can be modelled on Table 3.1, Methods of Measuring
Biodiversity, on page 90 of the textbook.
During Reading
• Divide the class into groups of four, and have group members compare their lists, so
that all members have the same terms and headings listed. Each member of the group
will be responsible for finding definitions or explanations of one quarter of the terms
and headings listed. Each member of the group reads the corresponding portion of
the textbook and fills in the second column of the table for the parts that he or she is
responsible for.
After Reading
• Monitor comprehension and summarize. Group members can share their explanations
with each other, and ask clarifying questions to ensure that everyone understands
the main idea of each chunk of text. Students can copy each explanation or rewrite it
in their own words, so that the second column of everyone’s table is complete. After
reflecting on the explanations, each individual student can complete the third column,
by creating an illustration for each term or heading.
Using the Images
• Ask students to examine Figure 3.1, on page 89 of the student textbook, and describe
the habitat of the shark. Based on the appearance of the shark and its habitat, what do
students suppose that it eats? How do they think it might hunt?
• In Figure 3.4, on page 92, what can students infer from the map, photograph, and
caption about the species found in the Carolinian forest? What are the species’ unique
and specific requirements? What can students infer from the map, photograph, and
caption about the eastern massasauga rattlesnake’s habitat requirements?
• Have students examine Figure 3.5, on page 93, carefully and determine how many
different species of fish there are in the small area shown in this photograph.

978-0-07-072367-2 Chapter 3 Biodiversity • MHR TR-1-71

 Assessment FOR Learning

Evidence of Student
Tool Understanding Supporting Learners

Selected Response Students define biodiversity • Use the Word Origin strategy from the Study Toolkit on page 88 to
Learning Check and explain one method of define biodiversity.
questions, page 92 measurement. Students explain the • Have students use the photographs in Table 3.1, Methods of
importance of wetlands. Measuring Biodiversity, on page 90, as cues to help them explain.
• Ask which has the greater biodiversity within the same region, a
wetland or mature forest? Provide some accompanying photographs,
or direct students to images from the text (for example, Figure 3.10,
on page 98, and Figure 3.22, on page 112). Very often, the wetlands
have greater diversity.

Selected Response Students select the appropriate • Direct students to Study Toolkit 4, Organizing Your Learning: Using
Section 3.1 Review method for sampling biodiversity Graphic Organizers, on page 567 of the textbook, for directions in
questions, page 94 and justify their choice. Students constructing a Venn Diagram to compare and contrast biodiversity
explain the importance of sampling measuring methods.
and data collection and how it • Ask students to choose a sampling method to determine an accurate
assists with ecosystem protection. representation of the actual number of students, furniture, and
equipment in the room. This activity can be done individually or in
groups. Students can plan their sampling method, and carry it out if
you wish.
• Have students form a line in the classroom. At one end is, “Sampling
is very important in ecosystem protection.” At the other end is,
“Sampling does not help protect ecosystems.” Direct students to
place themselves along the line. Then fold the line in half, so that
pairs of students with opposing views are facing each other. Have
the resulting pairs of students discuss the issue.

Activity 3-2, Students accurately record data and • If data recording is not a priority because students have done this
Biodiversity Index, make biodiversity calculations. task elsewhere in the unit, have students work in groups and record
page 93 their data on chart paper or mini whiteboards.
• It will probably be easier (and quicker) for students to record the
information in column 3 in the following way (assuming beads
were used):
Red = 3
Blue = 2
White = 5
Total number of organisms = total number of beads in all containers.

TR-1-72 MHR • Unit 1 Sustainable Ecosystems 978-0-07-072367-2

Instructional Strategies
• As a class, measure the biodiversity of the schoolyard, or a nearby park. Organize
students into groups of two to four, and have the students in half the groups use
quadrat sampling, and the others use transect sampling. After returning to the
classroom, compare the results of both methods, and have students decide which
method they thought was better for the schoolyard. Students can briefly present their
results to the class. This activity will appeal to students with a variety of learning styles.
As much as possible, create groups that include students with strengths in many areas.
• DI Spatial learners can create a postcard or sports card for a Canadian hotspot or
species at risk. Students may need some time to do research on the Internet before
creating their product.

Activity 3–2 Biodiversity Index (Student textbook page 93)

Pedagogical Purpose
This activity will demonstrate how biodiversity is calculated, by allowing students to
make their own calculations using a model of an ecosystem.

Planning

Materials Model ecosystems provided by you

Large number of coloured beads or other very small objects, such as dried beans or pasta (20–30 each of
10 different colours if possible)
Plastic containers of some kind or large resealable plastic bags
Mini whiteboards (optional)

Time 45 min

Background
Canada has 15 terrestrial and 4 aquatic ecozones. Visit www.scienceontario.ca to find
out more about each one, including the plants and animals that are native to each. As a
general rule, the farther north an ecosystem is, the less diverse it is.
Activity Notes and Troubleshooting
• You can assign each bag a name, such as “Arctic Cordillera” or “Boreal Plains,” and
place appropriate numbers of each “species” in the bags. Alternatively, to simplify
preparation, you can label the bags “Ecosystem A,” “Ecosystem B,” and so on. If you
decide to set up each bag to represent an actual ecosystem,
visit www.scienceontario.ca to learn about the species present in each.
• You could use any type of counter you wish, such as dried beans and pasta or coloured
bits of paper with different symbols—whatever is most cost effective and easily
available as long as you have a sufficient number of shapes and colours to represent the
number of species you want to have.
• Use large resealable plastic bags, so that students can flatten out the contents and
count them without having to dump out the contents. You could write on the outside
of the bag with a permanent marker. Plastic resealable bags can easily be stored and
transported for future use.
• Students may obtain slightly different results for a given ecosystem, due to difficulty
counting large numbers of small items in a bag. If this difference occurs, remind them
that this will also be the case for real life ecosystem sampling, and talk with them
about ways to obtain the best possible data, including averaging the results of several
counts.

978-0-07-072367-2 Chapter 3 Biodiversity • MHR TR-1-73

 Additional Support
• Decide which set of skills and knowledge are important to you and your class before
setting aside the time for this activity.
• If you want students to practise their data-collection skills, then you might want to
make sure each group records the information for all of the ecosystems themselves,
and each student has a made their own copy of the data in their notes.
• If you are only interested in the concept attainment (because students have had
other opportunities to record data), then you may want to conduct this activity
where the groups share their information with the class.
• In this case, you might want to use mini whiteboards, and summarize the
information at the front of the class.
• Students could still copy the summarized information into notes.
• Some students may find the headings on the table confusing. For those who do,
have them use the headings “Ecosystem,” “Number of Colours,” “Number of Each
Colour,” “Total Number of Beads,” “Number of Colours/Total Number of Beads”
to organize their observations. After students have collected their data, have them
replace the headings in their table with the original headings.

Answers
1. Students’ answers will depend on how the ecosystems were prepared. The
ecosystems with the highest biodiversity could possibly include the Southern
Ontario Wetland or Carolinian forest.
2. The strengths are that biodiversity is represented as a simple number. The weakness
is that it is unfair to compare very different ecosystems such as an Arctic ecosystem
with the Carolinian forest.
3. An abiotic factor could be the lowering lake levels that are drying up a shoreline
wetland. A biotic factor could be the introduction of an invasive species such as
purple loosestrife.

Learning Check Answers (Student textbook page 92)

1. Biodiversity is the number and variety of organisms found in a specific region.
2. Methods to measure biodiversity include canopy fogging (spraying a low dose of
insecticide up into the top of a tree, and collecting the insects for observation),
quadrat sampling (counting species in a marked area), transect sampling (recording
the type and number of species along a transect line at set intervals), and netting
(capturing, identifying, measuring, genetically analyzing, and tagging birds and bats
in ecosystems).
3. Scientists should record information about biodiversity to protect Earth’s
biodiversity. It is also helpful for land-use planners to know the location of
different species.
4. When ecosystems are protected, developers are not allowed to use the land for
building houses or industries, so the ecosystem’s biodiversity is preserved.

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Section 3.1 Review Answers (Student textbook page 94)
Please see also BLM 3-3 Section 3.1 Review (Alternative Format).
1. Students’ sentences will vary. A possible example is, “It is important to protect an
ecosystem so its biodiversity will be maintained.”
2. Both quadrat sampling and transect sampling involve counting species in specific
areas. In quadrat sampling, species are counted in an area marked with a piece of
plastic or stakes and string. The counting is repeated to ensure the representation
is accurate. In transect sampling, a transect line is marked at set intervals, and the
species found at each interval are observed and counted.
3. canopy fogging
a. The advantage of canopy fogging is that it is an effective way of collecting
information about the biodiversity of insects. The disadvantage is that insecticide
is used, which could harm some insects and other animals or vegetation in the
ecosystem.
b. Students’ answers will vary. Some students might say that they would use one of
the sampling methods (quadrat or transect) because there is no direct contact
with the species.
4. Information about biodiversity is used to protect Earth’s ecosystems, and scientists
need funding for their research.
5. Lake Malawi is home to about 1000 species of fish. This lake is about the same size as
Lake Erie, but Lake Erie has only about 150 fish species.
6. Students’ answers will vary. Scientists may not have an accurate count of the number
of species on Earth because insects and animals move around and hide, making
them difficult to study. Many ecosystems are also in remote or inaccessible locations.
7. Students might say that most of the world’s hotspots are in tropical areas because
there is less development and industry in the developing nations where these
hotspots are located or because more species on Earth are adapted to live in warm
climates than in cold climates.
8. Canada has initiatives to protect ecosystems in developing nations because
protecting all ecosystems is important for Earth’s biodiversity.

978-0-07-072367-2 Chapter 3 Biodiversity • MHR TR-1-75

 Section 3.2 Communities (Student textbook pages 95 to 99)

Specific Expectations In this section, students will learn that species live in communities where relationships
• B1.1 assess, on the basis of among different species are very important. Students will be able to explain in what ways
research, the impact of a factor keystone species are significant in maintaining an ecosystem through their relationships
related to human activity with other species. Students will understand that ecosystem engineers are species that
• B2.1 use appropriate alter a landscape, and they are part of the natural succession that occurs over time.
terminology related to
sustainable ecosystems, Common Misconceptions
including, but not limited to:
• Students may have seen television and magazine advertisements that have led
bioaccumulation, biosphere,
diversity, ecosystem, equilibrium, them to believe that preventing forest fires protects the wilderness and wildlife. In
sustainability, sustainable use, fact, forest fire prevention and suppression are important to protect communities and
protection, and watershed industry, but do not necessarily protect the forest. Fire is a natural and important part
• B3.5 identify various factors of the boreal forest succession and regeneration cycle.
related to human activity that
• Students may believe that captive breeding programs are capable of increasing
have an impact on ecosystems,
and explain how these factors populations of animals so that species will no longer be at risk. However, captive
affect the equilibrium and breeding programs are not always successful. Many species do not respond well to
survival of ecosystems captive breeding programs. In particular, large predators that must learn hunting
skills from their parents and migratory birds are not as successful in captive breeding
programs as some other species are.

Background Knowledge
The impact of a keystone species is often greater than would be expected. If a keystone
species is removed from an ecosystem, the entire ecosystem may shift or collapse.
Grizzly bears are a keystone species in the transfer of nutrients from the ocean to the
forest. They do this by consuming salmon. Elephants are a keystone species in that they
prevent shrubs and brush from encroaching on African grasslands.
Some species, called ecosystem engineers, actually transform their ecosystem. For
example, trees that grow in direct sunlight create a shady environment for other types of
vegetation. In forest succession, birch, poplar, and maple trees are well adapted to take
advantage of open spaces. Birch and poplar are short-lived species and do not thrive well
in shady forests, while maples will continue to grow in a mixed forest. Other species of
trees require shade in order to establish themselves. White pine and red oak are often
planted with a cover or nurse crop to help them establish.

Literacy Support
Using the Text
Preview vocabulary with English language learners. Use an analogy to compare
ecosystem communities to human communities with which students are familiar, such
as their school. The Sense of Value feature on page 96, explaining what a keystone is, can
help students understand and remember the term keystone species.
Before Reading
• Have students scan the section and create a list in their notebook of Key Terms, as well
as other words that they find in headings or definitions that seem important. Tell them
that as they read, they will be looking for relationships among these ideas to create a
concept map. Students can create their lists on their own or in pairs. Have students list
approximately 20 terms.

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 • ELL English language learners can work with a fluent English speaker. Have them
also identify words that they do not understand, and use the Glossary or ask their
partner for clarification.
• Refer students to the concept map in Study Toolkit 4, Organizing Your Learning:
Using Graphic Organizers, on page 566 of the student textbook.
During Reading
• As students read through the section, they should reflect on how they will link each of
the terms in their lists in their concept map. Students may want to record some ideas
in a rough draft.
After Reading
• To help students differentiate between concepts and linking words, have students
brainstorm some of each as a class. Create two lists on the chalkboard and ask students
to describe the differences they see between concepts and linking words.
• Have students create a concept map. Students may want to attach two pieces of
notebook paper to make a larger piece of paper, or work in a group and use chart
paper, for this activity. It is useful to have some coloured pencils or markers on hand.
Using the Images
• Have students examine the two illustrations in Figure 3.7, on page 96, and list as many
differences as they can in their notebooks. Have students state in their notebooks
whether they think the sea urchin population affects the otter population or the otter
population affects the sea urchins, and explain how. Ask students how a change in the
sea otter population might affect populations of other organisms in this ecosystem.
For example, fewer sea otters and less kelp could cause a decline in the populations of
small fish, and cause predatory birds, such as eagles, to eat more seabirds.
• How many phases of succession can students observe in Figure 3.10, on page 98?
Students can write about how the beaver pond has facilitated or changed each of these
phases. Students could also use a flowchart or a cause-and-effect diagram.

Assessment FOR Learning

Evidence of Student
Tool Understanding Supporting Learners

Selected Response Students explain the importance • Provide an illustration of a keystone in an arch. Ask, “If the
Learning Check of captive breeding and define keystone of the arch is removed, what happens?” Ask students why
questions, page 97 keystone species. scientists choose this analogy to describe why some species are
crucial to the health of their ecosystem.

Selected Response Students identify a keystone • Direct students to Study Toolkit 4, Organizing Your Learning: Using
Section 3.2 Review species and describe its role in an Graphic Organizers, on page 567 of the student textbook, for
questions, page 99 ecosystem. directions to construct a Venn diagram.
• Direct students to answer question 3 using a cause-and-effect
diagram. Refer them to Study Toolkit 4 on pages 566 and 567.
• Direct students to illustrate the situation described in question 4
using a flowchart or a concept map to help them answer. Refer to
Study Toolkit 4, on pages 566 and 567.
• For question 5, have students rank each of the species from least
charismatic to most charismatic.

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 Instructional Strategies
• DI Any video about one of the keystone species mentioned in this section would
be an effective way to introduce or conclude the section, especially for spatial learners
and for students who are not familiar with the species.
• Have students research on the Internet the Toronto Zoo’s captive breeding programs.
Assign an animal from this program to a pair of students, and each pair will design a
poster outlining the captive breeding program for their animal. Include information
such as where the animal’s native habitat is, and what other organizations are involved.
This activity will appeal to spatial learners, as well as naturalistic and interpersonal
learners.
• Students can construct a model of the succession facilitated by beavers. Leave the
choice of materials to the students, but you may wish to put a price limit on the
project.
• As an alternative to building a model, students can create a comic or graphic novel
describing the succession facilitated by beavers. There are many software programs
available to schools for making comics and movies. Students can also add music to
their comic or graphic novel using computer movie-making software.
• DI ELL Have linguistic and intrapersonal learners research other ecosystem
engineers and prepare a brief written report, or a creative oral or multimedia
presentation. If English language learners have information about ecosystem engineers
in their country of birth, ask them to share it with the class.

Learning Check Answers (Student textbook page 97)

1. It is important to preserve the biodiversity of communities in order to protect the
species in that community because species depend on the relationships among
organisms that exist within the community.
2. A keystone species greatly affects the population numbers and health of an
ecosystem. Sea otters are a keystone species because they control the number of sea
urchins, which allows kelp to survive.
3. A captive breeding program re-introduces a species that is in danger of becoming
extinct into its natural environment to increase its population.
4. Black-footed ferrets use the burrow system made by the prairie dogs, so when
prairie dog populations suffered, so did the ferret population.

Section 3.2 Review Answers (Student textbook page 99)

Please see also BLM 3-4 Section 3.2 Review (Alternative Format).
1. A community includes all the populations of different species that interact in a
specific area or ecosystem.
2. Students’ Venn diagrams should show the following similarities and differences:
The removal of both dominant species and keystone species results in decreased
biodiversity within the ecosystem. However, dominant species are very abundant
and have a large biomass, and they are always primary producers. Keystone species
are generally not abundant, and they can be plants or animals.
3. Students may say that removing a rare species would not change the ecosystem
much because if there is only a small number of this species, other species probably
do not depend on it for survival. A dominant species, however, is very abundant and
has a large biomass, so more species would depend on it.
4. The beetle would be classified as an ecosystem engineer because it causes a dramatic
change to the landscape and creates a new ecosystem.

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5. Students’ answers will vary, but may include the following ideas:
a. The polar bear could be considered a charismatic species because it is cute and
can interact with people.
b. A fern probably would not be considered a charismatic species because it is not
personified.
c. A blue whale could be considered a charismatic species because it is huge and
strong.
d. An earthworm would not be considered a charismatic species because it does
not capture most people’s attention and is not usually cared for as a pet.
Students may feel that charismatic species should not receive more attention than
other species at risk because all species at risk deserve equal attention.
6. Succession refers to the changes that occur over time after a disruption in
an ecosystem.
7. Beaverpond basket-tail dragonflies and wolves both benefit from the changes that
beavers make to their environment when they build dams. The dragonflies live in
beaver ponds and the wolves live in the meadows that form after the ponds have
dried up.
8. An ecosystem engineer is like an urban planner who develops housing communities
in formerly rural or untouched areas.

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 Section 3.3 Threats to Biodiversity
(Student textbook pages 100 to 109)

Specific Expectations In this section, students will learn that threats to biodiversity include habitat loss, the
• B2.1 use appropriate introduction of alien species, overexploitation, and breaking the connectivity among
terminology related to ecosystems. Students will understand that draining wetlands can result in habitat loss.
sustainable ecosystems, Students will be able to explain that extinction is a natural event that has occurred
including, but not limited to:
throughout Earth’s history, and that current extinction rates may be accelerated due to
bioaccumulation, biosphere,
diversity, ecosystem, equilibrium, human activities.
sustainability, sustainable use,
protection, and watershed Common Misconceptions
• B2.5 analyze the effect • Students might believe that all invasive species enter the ecosystem by accident.
of human activity on the Zebra mussels did enter the ecosystem by accident, but many other species, such
populations of terrestrial as dandelion, were introduced intentionally. Noxious weeds, for example, were
and aquatic ecosystems by introduced by settlers to remind them of the wildflowers from home.
interpreting data and generating
graphs • Students may not be aware that the most significant rates of extinction are
• B3.5 identify various factors probably occurring in our oceans. We tend to think only of terrestrial animals that
related to human activity that evoke an emotional response, such as polar bears. However, overfishing is the leading
have an impact on ecosystems, cause of the decline in populations of large predatory fish, including tuna, marlin, and
and explain how these factors swordfish. Some estimates report that populations have declined as much as
affect the equilibrium and
90 percent over the last 20 years.
survival of ecosystems
Background Knowledge
Wetlands are often drained for agriculture. The Holland Marsh in Ontario now supplies
food for a large portion of Canada, not just Southern Ontario. Agriculture in this
area dates back to the 1920s, and the drainage system was completed in the 1930s.
What was gained in agricultural productivity was lost in watershed management. The
natural floodwater protection provided by marshes and wetlands was not in place when
Hurricane Hazel struck in 1954, and many people on the marsh lost their homes.
Extinction occurs when a species is no longer able to survive in changing conditions
or against superior competition. The apparent acceleration of extinction rates has been
called the biodiversity crisis. Not too long ago, our attitude toward extinction was much
more cavalier than it is today. In the late 1800s and early 1900s, leading museums often
hunted down a species on the verge of extinction to the very last specimen. They did this
so they could say that they had the last known member of a species.
The debate on the seemingly imminent extinction of the popular yellow banana is
ongoing. On one hand, the banana is a primitive plant and may have been naturally on
its way out. On the other hand, as a result of human activity, the bananas we consume
are most often from large monocultures and therefore lack genetic diversity. The jury
is still out on whether commercial propagation has doomed the banana into early
extinction or bought us a few more years to enjoy this fruit.

Literacy Support
Using the Text
Before Reading
• Make connections to prior knowledge. Talk with students about the meaning of each
Key Term and record their ideas on the chalkboard. Encourage others to question or
refine the ideas. If students need help, they can refer to the definitions in the textbook.
• Once you have recorded a definition for each term, have students list examples of each
term. Record these under the definitions on the chalkboard. Students will find some
definitions in the textbook, including the images.

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During Reading
• Have students work in groups of four. Each group member identifies the causes and
effects that are associated with one of the threats, and then explains these to the
group. Refer students to Study Toolkit 4, Organizing Your Learning: Using Graphic
Organizers, on page 566 of the student textbook. Students can record on BLM G-33
Cause-and-Effect Map.
• ELL English language learners may benefit from working in pairs for one threat.
After Reading
• Have each student summarize the causes and effects associated with all four threats
using a format of their choice. Some may wish to record point-form study notes.
Others may want to create a concept web.
• Alternatively, students could summarize in their groups by creating a concept web for
the section as a placemat activity on a large sheet of paper. The placemats could be
displayed in the classroom for all students to refer to.
Using the Images
• Ask students to compare the cut areas in Figure 3.11, on page 100, with the forest on
the distant slope to the right. Ask, “How has the forest regrown just above the clear-
cut area compared with the slope on the right?” What other effects of deforestation
can students notice in the picture? (for example, soil erosion) The observations can be
recorded on the chalkboard during class discussion.
• For Figure 3.12, on page 101, ask students how the forest loss compares between
Africa, and Central and South America. Ask, “Why are so many more countries
listed for one region?” Do students notice that any countries are missing from the
list? Ask, “What other information might be needed in order to compare one region
with another, and where can you find this information?” (For example, areas of
deforestation could be found in an atlas or on the Internet.) The answers can be
recorded on the chalkboard as a brainstorm session, or students can record the
answers in their notebooks.
• As students examine Figure 3.16, on page 104, ask why they think the cod catch went
up in the 1960s: “Was it a natural increase or human-induced?” Students should
verbally describe what they think happened. Ask, “In what ways can this pattern be
compared to a predator-prey relationship?”
• For Figure 3.17, on page 105, have students make the last connection. What benefits
do the trees provide for the salmon? (They reduce run-off, clear shaded streams,
and provide oxygen to the ecosystem.) Have students copy the diagram into their
notebooks and include the last connection, or distribute BLM 3-5 Ecosystem
Connections, for them to complete.

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 Assessment FOR Learning

Tool Evidence of Student Understanding Supporting Learners

Selected Response Students explain the significance of habitat • Suggest that students think about a concrete example as
Learning Check loss and the possible effects of introducing they answer questions 1 and 3.
questions, page 103 an alien species. • Have students do an Internet search to find more
information on the significance of wetlands. Suggested
search queries include Ontario wetlands and Ontario
wetland habitat.

Selected Response Students explain the human impacts that • For question 2, refer students to Science Skills Toolkit 1,
Section 3.3 Review cause habitat loss. Students also explain the Analyzing Issues—Science, Technology, Society, and the
questions, page 109 significant impact of invasive species and Environment, on page 529 of the student textbook. They
what can be done to control invasive species. can also use BLM G-16 Tips for Investigating Many-
Students consider different perspectives as Sided Issues; BLM G-17 Worksheet for Investigating
they make environmental decisions. Issues; and/or BLM G-18 Decision-Making Organizer,
to help them consider differing viewpoints fairly.
• In groups of four, have students brainstorm and answer
questions 3 and 5 on chart paper. Display the answers to
share with the rest of the class. Encourage students to
use real examples in their T-charts and slogans, for which
Internet access may be helpful.
• Students can use BLM A-13 Venn Diagram Assessment
Checklist, to guide their work in question 6.
• For questions 7 and 8, have students do some brief
research on the Internet to learn more about the concepts.

Activity 3-3, Alien Students extract the necessary information • Refer students to the Interpreting Tables strategy in the
Invasions, page 104 from a table and decide on the appropriate Study Toolkit on page 88.
application for a given scenario. • Ask students to identify and locate specific information
that they need for the activity. You might ask the following
questions: “How large is the infestation? (Locate that
information on the left side of table.)” “What is the density
of the infestation? (Locate that information across the top
of the table.)” “Where do the columns and rows intersect?”

Activity 3-4, Plants Students estimate numerical values from the • Refer students to Math Skills Toolkit 3, Organizing and
at Risk, page 108 bar graph. Students calculate percent and Communicating Scientific Results with Graphs, on page 557
write persuasively about species at risk. of the student textbook.
• Allow students to use computers to design their flyers.
• Allow English language learners and others to present
most material visually, with little text.
• Provide students with a template for a persuasive
argument. See BLM 3-6 Writing a Persuasive
Argument, or BLM 3-7 Writing a Persuasive Argument
(Alternative Version).

Instructional Strategies
• Book a computer lab and have students find information about recent extinctions.
Using an LCD projector, share some of the websites that students have found with the
rest of the class.

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• Have a “Town-Hall Meeting” role-play about the draining of a local wetland for
development. The interested parties include the mayor and town council, the
developers, the citizens concerned about West Nile virus, the Federation of Ontario
Naturalists, and the Ontario Federation of Agriculture. Allow students to select their
own groups as much as possible. Each group will present their side to the town council
in order to persuade them to allow, or dissuade them from allowing, the development
of the wetland. Students may need a little time to prepare, and they may want to do
some Internet research overnight. Although this is not strictly a debate, students may
want to prepare their arguments and anticipate others’ arguments using BLM G-15
Debate Organizer.
• Read The Lorax, by Dr. Suess, aloud to students, which will be beneficial to auditory
learners and English language learners. Alternatively, watch The Lorax DVD with the
subtitles on. Afterward, have students create their own poem, rap, song, or picture
book about the environment.
• Real World Investigation 3-A, on page 117 of the student textbook, allows students to
apply what they have learned about threats to an ecosystem to consider the effects of
introducing zebra mussels into Lake Ontario.
• Making a Difference, on page 101 of the student textbook, introduces students to the
role that commitment can play in creating environmental change and asks students to
consider what they have learned and make their own commitments.
• In the Case Study, on pages 106 and 107 of the student textbook, students explain the
role that traditional ecological knowledge can play in determining sustainable use of
natural resources.

Activity 3-3 Alien Invasions (Student textbook page 104)

Pedagogical Purpose
This activity allows students an opportunity to practise interpreting graphic text and
applying the information. Students also consider the roles of some common methods of
controlling alien species.

Planning

Materials Paper (any size, including chart paper)

Coloured pencils and markers
Computer lab and internet access (optional)
LCD projector (optional)

Time 45–55 min plus an additional 40–90 min if students create Web pages

Background
Purple loosestrife may have been introduced accidentally in ship ballast. It has also been
used as a horticultural plant. The horticultural variety was once thought to be sterile, but
it often is not.
Activity Notes and Troubleshooting
• If time is limited, make sure that students understand that they have to complete only
an outline of a poster.
• Provide these guidelines for making a poster:
• Divide a paper into six equal sections:
• One section is for the title, and one is for the location and directions.
• Two sections are for illustrations or graphics.
• Two sections are for information, with no more than seven bullet points each.
• Students should be able to complete this activity individually.

978-0-07-072367-2 Chapter 3 Biodiversity • MHR TR-1-83

 Additional Support
• Complete this activity in groups of four, and have each group present their poster to
the class.
• Allow students the option to use a computer to create a Web page instead of a poster.
They may want to use publishing software or web-design software.
Answers
1. Different methods of controlling purple loosestrife include digging and pulling,
chemical control, cutting, and biological control.
2. The conservation officer should choose digging and chemical control.
3. For larger infestations you would not want the control methods to damage native
plants and animals; therefore, a variety of methods would be necessary to remove
purple loosestrife from different situations.
4. Students’ poster designs will vary. Tasks should include digging and pulling,
chemical control, and cutting. Students should mention that controlling purple
loosestrife is important to keep the plants from forcing out native wetland species
and changing the wetlands ecosystem.

Activity 3-4 Plants at Risk (Student textbook page 108)

Pedagogical Purpose
This activity allows students an opportunity to practise interpreting graphic text and
applying the information. At the same time, students internalize the meanings of the
subcategories by applying their knowledge to effect environmental change.

Planning

Materials Calculator
BLM 3-6 Writing a Persuasive Argument (optional)
BLM 3-7 Writing a Persuasive Argument (Alternative Version) (optional)
Letter- or legal-sized paper
Coloured pencils or markers
Canadian dictionary

Time 50–55 min

Background
Species at Risk is Canada’s system of categorizing the degree to which a species is in
danger of becoming extinct. Other countries use only one or two categories—such as
endangered or threatened. In general,
• extinct means not existing anywhere on Earth
• extirpated means no longer existing in a particular area
• endangered means a severe reduction in numbers over the past 10 years
• threatened means a significant reduction in numbers over the past 10 years
• of special concern means susceptible to a known threat, for example, an animal that
feeds primarily on an organism that is significantly declining in numbers
For more specific definitions, see www.scienceontario.ca.
Activity Notes and Troubleshooting
• Students may not be able to find the definitions in the dictionary, as they pertain to
wildlife and plants. You may have to use the Internet to access Environment Canada’s
definitions of these terms.
• Have students use a ruler to help estimate the number of endangered and threatened
species from the graph.

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• Guidelines for making a flyer:
• Divide a paper into six equal sections.
• One section is for the title, and one is for the location and directions.
• Two sections are for illustrations or graphics.
• Two sections are for information, with no more than seven bullet points each.
• Provide students with a template for making a persuasive argument, such as BLM 3-6
Writing a Persuasive Argument.
Additional Support
• Allow students to complete their flyer on a computer using publishing software. If you
do so, provide an electronic copy of the template for students to use.
• Practise making a persuasive argument with the class. For example, ask students to
form a persuasive argument convincing their parents to allow them to stay out later
with their friends this Friday.
• Some students may benefit from the additional support of BLM 3-7 Writing a
Persuasive Argument (Alternative Version).
• ELL Together, make a list of words that can be useful in a persuasive argument in
general, and in this persuasive argument in particular. These can be words associated
with cause and effect, such as if…then, so, because, therefore, result, as well as the Key
Terms of this unit. English language learners may want to create a cause-and-effect
map first, and possibly develop the ideas they include into a written argument later.
Answers
1. The endangered category contains the most plant species, and the extinct category
contains the least plant species.
2. Approximately 2 percent of the plant species are endangered, and 0.9 percent are
threatened.
3. Students’ flyers will vary. Main points should include what deerberry shrubs look
like, how they contribute to their ecosystem (they are an important food source for
deer and other animals), why they are at risk, and how they can be protected by
hikers staying on the paths. Students might also include images of deerberry plants
and the park trail routes.
4. Students’ answers will vary. Answers could be that the endangered plant should be
saved because it is more at risk of becoming extinct or that the threatened plant
should be saved because there is a better chance of bringing back the population so
it is no longer at risk. Students might argue that the solution is to find funding to
save both plants.

Learning Check Answers (Student textbook page 103)

1. Habitat loss is when an ecosystem is altered by events due to natural disasters or
human activities to the point where many species can no longer live there.
2. Wetlands are drained for farming or for building homes and other buildings, and
sometimes for mosquito control.
3. Alien species often do well when they are released in a new part of the world
because they often have no natural predators to control their population, they can
out-compete native species for food, and they can take over native environments.
4. Round gobies might function effectively as predators and competitors in the Great
Lakes because within 10 years of their arrival, they were found in all five Great
Lakes, and their population in the western Lake Erie region is estimated to be in
the billions.

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 Section 3.3 Review Answers (Student textbook pages 109)
Please see also BLM 3-8 Section 3.3 Review (Alternative Format).
1. Human activities that destroy habitats include deforestation, draining wetlands, and
damming rivers.
2. Students’ answers will vary. They may feel that the creation of jobs is not worth the
habitat destruction that will result from draining the wetland, and perhaps they
could develop a plan to create jobs by starting an environmentally-friendly project.
3. Students’ answers may vary.

Eliminating a Naturally Invasive Species

Advantages Disadvantages

Invasive species upset the equilibrium of an Complete elimination might not be possible
ecosystem, causing problems for the native if species is wide spread.
species. Elimination methods might cause more harm
Invasive species can out-compete native than good (such as using cane toads to
mussels and other native organisms in the control rabbit populations in Australia).
lakes. Very expensive. Money might be better
Will protect native species and their spent on an environmental project that can
ecosystem. be successful.
Will ensure the ecosystem stays in balance.

4. Overexploitation, such as overhunting and overfishing, can threaten biodiversity

because the population of species can become very low, or the species could
even disappear.
5. Students’ slogans will vary. Ensure that they include three human activities that have
a negative effect on biodiversity, such as overhunting, overfishing, deforestation,
and pollution. A possible slogan might be “If we overhunt, overfish, or overcut, we’ll
overdo it!”
6. Students’ Venn diagrams should include the following ideas: In both background
extinction and mass extinction, species become extinct. In background extinction,
some species become extinct over a long period of time, but some new species
appear through evolution. In mass extinction, a sudden change makes Earth’s
ecosystems unsustainable, leading to the extinction of many or all species.
7. It is believed that mass extinctions are caused by sudden changes to Earth’s
ecosystems, such as an asteroid hitting Earth or an extended period of massive
volcanic activity.
8. The biodiversity crisis refers to the current rate of extinction being 100 to 1000 times
higher than a normal background extinction rate. Scientists believe that the crisis is
caused by human activity.

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Section 3.4 Restoration Ecology (Student textbook pages 110 to 116)

In this section, students will learn that restoration ecology includes reforestation and Specific Expectations
wetland restoration, the control of alien species, bioremediation, and bioaugmentation. • B2.1 use appropriate
Students will learn that the flow of nutrients through ecosystems can be interrupted by terminology related to
human activities, and restoration techniques can offset those interruptions. sustainable ecosystems
• B3.5 identify various factors
Common Misconceptions related to human activity that
• Students might confuse restoration ecology and conservation ecology. have an impact on ecosystems,
and explain how these factors
Conservation ecology is the predecessor; the focus is on rare and endangered species, affect the equilibrium and
mainly animals. Restoration ecology attempts to address extinction, food supply, survival of ecosystems
timber supply, the maintenance of clean air and water, and climate regulation.
Restoration ecologists consider many of the holistic benefits provided by a healthy
and diverse ecosystem.
• Some students may believe that reforestation projects restore a forest to its original
state. However, diverse mixed forests are replaced with monocultures, mostly because
it is more economical and practical to do so. Many species of trees found in mixed
old-growth forests are not easily cultivated and must seed themselves on their own.
Hemlock would be one such species.
• Students may not consider that there are any drawbacks to restoration ecology.
However, there are some. In bioremediation, plants are often used to soak up
contaminants in the soil. The plants are harvested and then incinerated. The problem
with this technique is that the toxins are now concentrated in the ash from the
incinerated plants. How should we dispose of it?

Background Knowledge
Environmental stewardship is defined as the co-operative planning and management of
a resource to meet the needs of a community. The original pine, maple, and oak trees in
York Region were cleared in the late 1800s for farming. In 1924, a tree-planting program
was established to reduce wind. The distinctive red pine plantations of York Region
were originally intended to promote the establishment of oak through succession. To do
this, the forest required manual thinning at 30 and 60 years. Unfortunately, this part of
the plan was forgotten over the generations, and the first thinning did not occur. Now
that the pine has sufficiently grown, we are starting to see some natural thinning from
blowdowns, and oak trees have started to re-establish themselves in the gaps.
When preserving or restoring an ecosystem, we have to be careful not to lock
ourselves into a historical ideal of what the ecosystem once was and neglect the process
of succession. Algonquin Park was originally intended to preserve the headwaters of
five major rivers that were important to the transportation of timber. The park has been
selectively logged since that time. Since the park is also heavily used by campers, and
it is surrounded by several communities, it is beneficial that Algonquin has not stayed
“frozen in time,” because its current state makes nature safe and accessible.
Unfortunately, restoration ecology is much more easily practised by regions with
stable governments and economies. It is mostly found in more developed countries
in the northern hemisphere. Restoration ecology is not often practised in the tropical
regions where there are more environmental hotspots at risk.

Literacy Support
Using the Text
Before Reading
• Preview text features. Have students create a three-column table in their notebooks.
Have students preview the section and list all the bolded words and headings in the
left column, leaving plenty of room below each one.

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 During Reading
• Monitor comprehension. While students are reading the text, they will locate and copy
two or three sentences that describe or define each term or heading into the middle
column of their table.
After Reading
• Make study notes. Using the context of how each term was used in the text, students
will come up with their own definitions and record them in the right column of their
table. Students can share some of their definitions with the class afterward.
• ELL Encourage students to ask about any terms they do not understand.
Using the Images
• For Figure 3.22, on page 112, ask students to describe the diversity in each of the four
photographs. Students can divide their notebook paper into four sections, and record
their observations for each photograph in the corresponding section on their paper.
• For Figure 3.27, on page 115, have students use the person and pickup truck to
estimate how deep the tar sands are at the location where the photograph was taken.
Students should describe the steps they think will be necessary before trees can be
planted again. Ask students where most of the soil nutrients lie in these northern
boreal forests. Ask, “After mining is completed, where have the nutrients gone? How
can they be replaced?” Students should make a sketch of this photograph in their
notebooks and answer the questions above or below their sketch.

Assessment FOR Learning

Tool Evidence of Student Understanding Supporting Learners

Selected Response Students explain the meaning of • To help students understand stewardship, use the example of
Learning Check stewardship and restoration ecology a family pet. Although not all students have pets, many will be
questions, page 111 including listing similarities and able to share their experience with the class. Ask students who
differences. in their home is responsible for taking care of the pet, feeding it,
and cleaning up after it. Ask students what other needs the pet
has. Is the student a good steward for the pet?
• Research and point out where restoration ecology projects are
occurring in your area. Describe what is happening. Ask students
how this is different from stewardship.
• Provide examples and non-examples of restoration ecology, and
have students work in pairs to categorize them.

Selected Response Students explain the steps involved • In addition to activities they take part in now, ask students to
Section 3.4 Review in the process of restoration ecology, list five things they could do on a daily or weekly basis that
questions, page 116 including its costs and benefits to the would contribute to environmental stewardship.
environment. • Have students answer questions 3 and 4 using a cost/benefit/
risk table. Remind students that the costs are not necessarily
financial. Students can work in groups and post their answers on
chart paper to share with the class.

Game Strategy Students connect the lesson they • Appoint one member of the group to record the number of chips
Activity 3-5, The learned from the game to ecosystems and points after each round, and then graph the data. What was
Common Good, and overexploitation of resources. the trend observed by each group?
page 113

TR-1-88 MHR • Unit 1 Sustainable Ecosystems 978-0-07-072367-2

Instructional Strategies
• Contact your local conservation authority or chapter of the Federation of Ontario
Naturalists, and find out if there are any tree plantings or other restoration projects
with which students can get involved. Encourage students to participate in these
events; they may even be able to pick up community service hours.
• Plan a trip to a local bog or wetland. Your school board’s outdoor education centre
may be able to assist with this field trip. This field trip may bring the content to life for
spatial, bodily-kinesthetic, and naturalistic learners.
• Have students research a local restoration project and prepare a brief report
or presentation.
• What if a portion of the schoolyard or local playground was set aside for
bioremediation to return it to a natural state? In small groups of three or four, have
students design a plan and outline the steps to follow for such a project. As an
extension, students could write proposals to the principal or town council and
present them.
• Enrichment—Have students apply what they have learned in this chapter as they carry
out the research outlined on BLM 3-9 Biodiversity in Ontario.

Activity 3-5 The Common Good (Student textbook page 113)

Pedagogical Purpose
This activity models what happens when a limited resource is shared without regulation,
which can result in overexploitation.

Planning

Materials Bingo chips or similar small items (100 per group)

Watch or clock
Paper to track points
Large cardboard (to go outside)

Time 15 min (maximum)

Background
There are many variations of this game; it is based on the ecological article “The Tragedy
of the Commons” written by Garrett Hardin.
Activity Notes and Troubleshooting
• The number of people in each group is not as important as making sure all the groups
have the same number of people. Any students who are not in groups can be assigned
the tasks of keeping score and replenishing chips.
• Bingo chips are preferable to other materials because they are smooth and flat and
difficult to pick up. It may be necessary to provide a smooth, sturdy surface, such as
cardboard or Bristol board.
• If there is not enough room in the classroom, find another location such as the library
or gym, or go outside.
• It might be interesting to try the activity a second time with uneven numbers in the
groups. What do students notice? What does that tell us about overexploitation and
sustainable use?

978-0-07-072367-2 Chapter 3 Biodiversity • MHR TR-1-89

 Additional Support
• DI In order to appeal to students who do not understand the point of the game,
collect and graph the data. Doing so will help the logical-mathematical students and
students whose background does not involve game strategy as part of their learning.
Discussing the answers with the class will also help to debrief the activity and help
students recognize what they can learn from it.
• Plot the data for number of chips collected in round 1 and the number of points for
each round. Ask, “Is there a trend to the data?” You may have to complete more than
three harvests.
• Enrichment—Ask, “Is there a point in the game when there will be no more chips to
harvest?” Students can extrapolate their graph to predict this.

Answers
Answers will vary depending on the behaviour of students and the results of the game.
Some students realize right away that they should never allow the remaining chips to go
below 50 and co-operate from the start.
1. The strategies that led to the greatest decline in a team’s resources were not
cooperating, taking too many chips, and not ensuring students had chips
in sets of 10.
2. The strategies that led to the highest number of points for a team were co-operating,
only taking chips in sets of 10, and never letting the pool go below 50 chips.
3. The strategies that provided the maximum points for an individual and a group are
different. An individual will get the maximum points if he or she gathers as many
chips as possible. A group will get the maximum points if they leave most of the
chips in the pool.
4. Resources might include trees, fish, or other renewable natural resources that need
to be sustainably harvested.

Learning Check Answers (Student textbook page 111)

1. Stewardship is the belief that all humans are responsible for the welfare of the
environment.
2. Daylighting is a restoration technique used by restoration ecologists to uncover
buried streams and rivers.
3. A series of ponds can improve water quality by capturing sediment, filtering water,
and providing habitat for wildlife. They are also an interesting feature for visitors.
4. Restoration ecology is a practical extension of stewardship where degraded or
destroyed ecosystems are restored to their natural state.

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Section 3.4 Review Answers (Student textbook page 116)
Please see also BLM 3-10 Section 3.4 Review (Alternative Format).
1. Students’ answers may vary, but they might include planting trees; getting involved
in projects to restore wetlands, shorelines, and species at risk; controlling alien
species; and bioremediation and bioaugmentation.
2. Human activities that create the need for restoration ecology include overhunting,
overfishing, deforestation, habitat destruction, and air and water pollution.
3. Nearly a century of brick making and mining had left the environment around the
Don Valley Brick Works very badly damaged. Rather leaving it as a wasteland, the
site was sold and restored. Now it is a cultural heritage park with three filtration
ponds, wetlands, a wildflower meadow, and other features. The Brick Works shows
that ecological restoration is possible and desirable in cities.
4. Students’ paragraphs will vary, but they may include the following idea: Petroleum
should not be extracted by deforestation and removal of soils because forests and
soils are important to sustain an ecosystem. Instead, people should rely less on fossil
fuels and instead use alternative sources of energy.
5. Some methods that can be used to eliminate alien species include introducing
another species to the environment that will kill the alien species (biocontrol) and
using chemicals such as poisons or herbicides.
6. A poisoning campaign would not be successful. The islands are too large to poison
all the rats at once so they would continue to breed. The poison would also harm
native and farm animals. Even if all the rats were killed, it would be very difficult to
prevent them from being reintroduced.
7. Students will most likely find that the campaign was successful; however, the
number of wildlife cases of rabies was beginning to rise again after 1998.
8. Bacteria have been used in restoration ecology to break down the oil from oil spills
that damage coastline ecosystems.

978-0-07-072367-2 Chapter 3 Biodiversity • MHR TR-1-91

 Real World Investigation 3-A Zebra Mussels in Lake Ontario
(Student textbook page 117)

Pedagogical Purpose
Students will analyze data and use the information to write an argument for a
specific purpose in the form of an editorial. Many students may assume that writing
and communication skills apply only to English class. Science is pervasive in the
news, literature, entertainment, and sports. Professional scientists must be able to
communicate their ideas and results clearly, and are expected to write well.

Planning

Materials Graph paper

Coloured pencils
Access to the Internet
BLM 3-11 Writing an Editorial (optional)
BLM 3-12 Real World Investigation 3-A Zebra Mussels in Lake Ontario (optional)
BLM 3-13 Peer Editing Template (optional)

Time 1 h 45 min—2 h 15 min

Some work could be done out of class.

Background
Zebra mussels originated in the Caspian sea. They arrived in the Great Lakes in the
1980s, probably when ships cleared their ballast. Zebra mussels do provide some
benefits: they help to clean and filter the water they live in; however, this benefit does not
seem to outweigh the nuisance they cause by disrupting food webs and outcompeting
native species.

Activity Notes and Troubleshooting

• Students may not understand the importance of writing in the science profession.
Clear and concise communication can be the difference between having a research
grant renewed or not. The people renewing the grant may not be scientists. Scientific
research may also influence public opinion and the creation of legislation. Those who
are writing the legislation may not be scientists, so the experts must be able to make
the writers understand the importance of an issue. Take the time to extend this activity
beyond what is on page 117.
• Talk about the importance of scientific writing and communication.
• Deconstruct a few editorials as a class.
• Encourage students to take time to do extra research.
• Show some news clips.
• Provide an opportunity to do some peer editing. Use some of the techniques from
Think Literacy, such as a pass-around.
• Make this assignment count toward a summative mark.
• Parents and students may see this activity as trivial. Point out that it is an opportunity
to stress the importance of, and encourage, good scientific communication. It is a
misconception that science is just about facts.

Additional Support
• Make sure students understand the difference between an editorial and a letter to the
editor. Bring in some newspapers and have students critique the editorials.
• Have students use BLM 3-13 Peer-editing Template, to edit each other’s work before
the final draft is completed.

TR-1-92 MHR • Unit 1 Sustainable Ecosystems 978-0-07-072367-2

Answers
Analyze and Interpret
1. The chlorophyll a seemed to decrease as the zebra mussels increased.
2. The zebra mussels are filter feeders and most likely consume phytoplankton.
Less phytoplankton will result in less oxygenated water and a decrease in the fish
population.
3. Populations of lake floor plants and food supplies could increase due to the zebra
mussels.
Conclude and Communicate
4. Students’ articles will vary. Points should include that zebra mussels are released
into the Great Lakes in ballast water from ships; that they crowd out native species
of mussels; that they eat food other species rely on; and that they change the
environment of the lake which kills fish and other aquatic species.
Extend Your Inquiry and Research
5. Students should include some of this information: The Ballast Water Control
and Management Regulations are Canada’s rules about how ballast water can be
used and disposed of by ships so that the spread of invasive aquatic species can
be controlled. The regulations, and similar regulations in other countries, were
written to meet a requirement of The International Convention for the Control and
Management of Ships’ Ballast Water and Sediments adopted by the International
Maritime Organization in 2004. The convention was later ratified by 30 countries,
including Canada, representing 35 percent of the world’s shipping tonnage.

978-0-07-072367-2 Chapter 3 Biodiversity • MHR TR-1-93

 Inquiry Investigation 3-B Balancing Populations and the
Environment (Student textbook pages 118 to 120)

Pedagogical Purpose
Students will investigate the factors that affect the equilibrium of a population using a
game as a simulation of the system. Students will then interpret the data that they have
collected and interpret the meaning.

Planning

Materials 2 sheets of white poster paper (32 cm × 32 cm each)

Ruler
Sharp pencil
32 squares of green sticky notes (4 cm × 4 cm each)
Bag of 100 checkers or similar objects (50 black and 50 red)
Calculator
Graph paper
BLM 3-14 Inquiry Investigation 3-B Balancing Populations and the Environment (optional)

Time TOTAL: 75 min

Safety Students should use caution when working with sharp pencils.

Background
There are many variations of this game. It is based on the ecological article “Tragedy of
the Commons” written by Garrett Hardin.

Activity Notes and Troubleshooting

• Students can conduct this investigation in groups of two or more. Some discussion
about wildlife management policies should occur.
• Students can complete a formal lab write-up of this activity; if they do not follow up in
this way or in a similar way, the significance of the learning may be lost.
• If there is time to spare at the end of class, ask students how they might simulate the
introduction of wolves and then play a game for that scenario.

Additional Support
• You may have to run a trial year that does not count to make sure everyone
understands the instructions.
• Save some “parks” and “hunting screens” from a previous class as spares, in case a
group has trouble making them.
• Use the word simulation instead of game to help impart the seriousness of the activity.
• ELL Place English language learners in groups with fluent English speakers to help
interpret the instructions.

Answers
Analyze and Interpret
1–3. The answers will vary depending on students’ results.
4. The population size is dependent on the resources available. Humans are different
than deer because we can import resources if there are not enough to meet the
needs of the population.

TR-1-94 MHR • Unit 1 Sustainable Ecosystems 978-0-07-072367-2

 5. Possible answers include the following:
a. Deforestation would decrease the food supply and then the deer population.
b. Reforestation would replenish the food supply and the population would increase.
c. Removing wolves might cause the deer to exceed the carrying capacity of their environment. The population would
increase and then crash.
d. Restricted hunting might keep the population stabilized enough that the deer would not exceed the carrying capacity.

Conclude and Communicate

6. Answers will vary depending on students’ results. Those groups with very low deer populations would not want to
introduce wolves.
Extend Your Inquiry and Research Skills
7. Students’ answers will vary. One commonly used method is to do a helicopter survey in midwinter when the deer are not as
mobile in deep snow, and there is less forest cover to obscure the count.
8. Answers will vary depending on students’ research. Ontario is a world leader in using computer simulations for forest-fire
prediction models.

978-0-07-072367-2 Chapter 3 Biodiversity • MHR TR-1-95

Chapter Review Answers (Student textbook pages 122 and 123)
Please see also BLM 3-15 Chapter 3 Review (Alternative Format).

Make Your Own Summary

Students’ graphic organizers should include the following key concepts. An example is provided below.

draining
deforestation habitat loss
wetlands

overexploitation

several number and about 2 million breaking

methods variety of species connectivity
of measuring organisms on Earth alien species

extinction
is natural,
measuring biodiversity threats
but may be
increasing

biodiversity

succession describes
increasing biodiversity ecosystem engineers
reforestation a series of changes in communities
(restoration ecology) alter an ecosystem
in an ecosystem

wetland restoration
offsetting relationships keystone dominant
interrupted among species species are
flow of species are maintain an very common
nutrients very important ecosystem primary
controlling through their producers
alien species relationships

bioremediation bioaugmentation

Reviewing Key Terms 9. Methods to measure biodiversity include canopy fogging

1. the biodiversity crisis (spraying a low dose of insecticide up into the top
2. restoration ecology of a tree, and collecting the insects for observation),
quadrat sampling (counting species in a marked area),
3. biocontrol
transect sampling (recording the type and number of
4. succession species along a transect line at set intervals), and netting
5. Bioremediation (capturing, identifying, measuring, and tagging birds and
bats in ecosystems).
6. captive breeding
10. A biodiversity hotspot is a relatively small area with a
7. biodiversity
very large number of species. Most hotspots are found in
Knowledge and Understanding tropical areas.
8. Maintaining biodiversity on Earth is important because 11. When the death rate of a species remains higher than the
nutrients and energy cycle through ecosystems, and birth rate for a long period of time, extinction occurs.
what happens in one ecosystem can affect cycles in other
12. The most recent mass extinction was the death of the
ecosystems. Organisms depend on each other and their
dinosaurs, when an asteroid is believed to have hit Earth
environment to survive.
65 million years ago.

TR-1-96 MHR • Unit 1 Sustainable Ecosystems 978-0-07-072367-2

13. The greatest mass extinction of all time is believed to 26. Humans have a responsibility to look after the biosphere
have occurred a massive volcano in Asia was active for because if species are lost, the ecosystem will not be able
an extended period of time. to sustain the remaining species, including humans.
14. No, because all species are connected and what happens 27. Dominant species have to be primary producers because
in one ecosystem can affect cycles in other ecosystems. they are extremely abundant and are in the first trophic
15. Langara Island was originally predator-free. The level of the food chain, which means that all other
populations of nesting sea birds declined when two alien organisms depend on them for survival.
species of rats, which were accidentally introduced by 28. Students’ analogies will vary. A possible example is many
ship, ate the birds’ eggs and nestlings. people waiting in five check-out lines at a busy grocery
16. Deforestation is a threat to biodiversity because forests store. One cashier going on a break will have little effect
are cleared and never replanted, which affects other on the customers. However, if all five cashiers went on
organisms that depend on the forests for survival. a break, customers would not be able to purchase their
groceries.
Thinking and Investigation
17. fish Application
29. Students’ answers will vary. Some students might feel that
18. a. Since wolves eat elk, the elk population would
captive breeding programs are worth it because they help
increase if wolves were eliminated. Therefore, since to restore an ecosystem. Re-introducing one species can
elk eat aspen trees, the aspen tree population would help many other species to survive.
decrease. The new aspen trees likely would not have
a chance to mature before they were eaten by the elk, 30. A; Keystone species generally do not have a large
so natural succession would not occur. biomass, but they greatly affect ecosystem health.
b. Students’ answers will vary, but they might say that if 31. Chemicals cannot be used because the chemicals will kill
wolves were re-introduced, the elk population would other species and destroy the ecosystem. Also, digging up
begin to decrease, and the aspen tree population or cutting the plants would be too time-consuming and
would begin to increase. expensive.
19. If the wolves were re-introduced, the number of beavers 32. Students’ answers will vary. The solution that is in place
would increase because the wolves would eat the elk that now internationally is to sanitize ballast water before it
were eating all the aspen trees. There would then be some is dumped.
aspen trees for the beavers to eat.
20. No, because native species are important to an
ecosystem.
21. Wildfires can regenerate growth and create a new
ecosystem.
Communication
22. The alien species might adapt to their surroundings and
become native species over a long period of time.
23. Students’ answers will vary. Examples might include
restoration methods such as reforestation, wetlands
restoration, and controlling alien species.
24. First, it is efficient and cost effective to have one
provincial agency that manages information about
Ontario’s biodiversity. Second, the centre’s database
provides a valuable and necessary resource for studying
and understanding Ontario’s biodiversity. Third, the
centre ensures scientists have the information they
need to manage our natural resources and protect
species at risk.
25. Humans have a responsibility to look after the biosphere
for other human beings and for other organisms.

978-0-07-072367-2 Chapter 3 Biodiversity • MHR TR-1-97

 Unit 1 Projects

Inquiry Project
Pollutants and Aquatic Ecosystems (Student textbook page 126)
Pedagogical Purpose
This investigation allows students to study the impact that humans can have on
the sustainability of an ecosystem. The pollutants in this investigation are common
substances resulting from the choices average people make for their homes and lifestyles.
This project is an opportunity for students to demonstrate the understandings and
skills they have developed in this unit.

Planning

Materials Salt 100 mL vinegar

100 mL beef or chicken broth 50 mL dish detergent
50 mL plant food 50 mL paint thinner
Seven 2 L soft drink bottles, or large jars, per group
Aquatic plants and organisms for each ecojar
BLM 3-15 Inquiry Project: Pollutants and Aquatic Ecosystems (optional)
BLM G-23 Data Table (optional)
• Purchase the aquatic supplies ahead of time.
• Ask students to bring in 2 L soft drink bottles for several days berforehand, until you have enough.

Time • 15–20 min to create the plan and data table

• 5–10 min to prepare each ecojar
• 10 min to apply the treatments to each jar
• 3–5 days to record the effects on each jar
• 1 period to prepare the presentation, and 1 period for all students to present their findings.

Safety Students should wear goggles.

Background
The choices we make every day to maintain our lifestyle can have direct impacts on the
environment. We salt roads and driveways in the winter, and the salt collects in storm-
water retention ponds. Car exhaust and coal-burning power plants contribute to acid
rain. Fertilizer and animal waste from our lawns as well as from farmland produce
run-off. Many household chemicals are intentionally and accidentally poured down the
drain, or washed down the driveway. When we think of pollution, we often consider
industry before we think of our own actions and choices.
Activity Notes and Troubleshooting
• Students should plan out the investigation several days before starting. They should
also come up with their own list of materials so you know what to acquire for them.
• You may want students to conduct this investigation on their own and purchase their
own supplies. To be equitable, supply some of the basic materials to get each ecojar
started, such as plants and other organisms.
• Often, students want to put fish or tadpoles in their ecojars. This activity is
discouraged, and may contravene local board policy, as the investigation will harm
and probably kill the animals, and will be extremely upsetting to some students.

TR-1-98 MHR • Unit 1 Sustainable Ecosystems 978-0-07-072367-2

• Decide on the type of audience to which students will present their findings, and let
them know. For example, will students be presenting to members of their community, or
to members of their class? Students’ presentations should be tailored to their audience.
• The assessment criteria are printed in the student textbook. Make sure students
understand what is required of them, are aware of the assessment criteria, and refer to
the list as they conduct their investigation and plan their presentation.
Additional Support
• DI Bodily-kinesthetic and spatial learners may prefer to use chart paper or to draw
their own overheads, as opposed to preparing a computer presentation.
• DI Intrapersonal learners and English language learners may feel uncomfortable
presenting their findings to the class. Provide the option of presenting to a smaller
group, or allow them to submit their presentation electronically by recording it
at home.
• Another option is to have students who are uncomfortable presenting in front of a
large group come in after school or at lunch to present.
Rubric

ACHIEVEMENT
CHART Level 1 Level 2 Level 3 Level 4
CATEGORY

Knowledge & Abiotic and biotic Abiotic and biotic Abiotic and biotic Abiotic and biotic
Understanding components of the components of the components of the components of the
ecosystem are described ecosystem are described ecosystem are described ecosystem are described
in limited detail. in some detail. in considerable detail. in thorough detail.

Thinking & Designed and executed Designed and executed Designed and executed Designed and executed
Investigation a procedure controlling a procedure controlling a procedure controlling a procedure controlling
appropriate variables appropriate variables appropriate variables appropriate variables
and using equipment and using equipment and using equipment and using equipment
and materials safely, and materials safely, and materials and materials safely,
accurately, with limited accurately, with some safely, accurately, accurately, with a high
effectiveness. effectiveness. with considerable degree of effectiveness.
Analyzed and interpreted Analyzed and interpreted effectiveness. Analyzed and interpreted
qualitative and qualitative and Analyzed and interpreted qualitative and
quantitative data to quantitative data to qualitative and quantitative data to
determine whether determine whether quantitative data to determine whether
evidence supports evidence supports determine whether evidence supports
predictions with limited predictions with some evidence supports predictions with a high
accuracy. accuracy. predictions with degree of accuracy.
Identified sources of Identified sources of considerable accuracy. Identified sources of
error and suggested error and suggested Identified sources of error and suggested
improvements in limited improvements in some error and suggested improvements in
detail. detail. improvements in thorough detail.
considerable detail.

Communication Data is recorded and Data is recorded and Data is recorded Data is recorded and
organized with limited organized with some and organized organized with a high
effectiveness. effectiveness. with considerable degree of effectiveness.
effectiveness.

Please also see BLM A-44 Unit 1 Inquiry Project Rubric.

978-0-07-072367-2 Unit 1 Projects Inquiry Project • MHR 99

 An Issue to Analyze
Protecting Ecosystems (Student textbook page 127)
Pedagogical Purpose
In the process of becoming scientifically literate, students are asked to draw on
their scientific knowledge and skills to assist them in making personal choices.
Scientifically literate students are able to actively participate in and contribute to their
neighbourhoods and communities. Being scientifically literate is part of being a good
citizen. For this issue, students are asked, “What could you do, as a member of this
community?”
This analysis is an opportunity for students to demonstrate the understandings and
skills that they have developed in this unit.

Planning

Materials Local newspapers and maps

BLM 3-16 An Issue to Analyze: Protecting Ecosystems (optional)

Time • 2 weeks (in and out of class) for research

• 1 or 2 periods for presentations

• Book a computer lab.

• Book a library period.
• Contact a local environmental group to see if they have resources that students
might use.
Background
Over 30 years ago, a small group of concerned citizens started a campaign that resulted
in the creation of one of the largest urban wilderness parks in North America. The
creation of Rouge Park by the Ontario government in 1995 was the result of many
years of public campaigning. Concerned citizens established the Save the Rouge Valley
Society (SRVS) in 1975, and they tirelessly campaigned for the creation of Rouge Park.
Thousands of citizens wrote letters and attended public meetings. Members of the SRVS
went even further to demonstrate their dedication to the park by establishing a volunteer
organization in 1989 called 10 000 Trees for the Rouge, which co-ordinates community
tree planting events every spring to help maintain and rehabilitate park habitats and
ecosystems. Rouge Park now connects the Oak Ridges Moraine greenbelt to Lake
Ontario. Rouge Park is an example of how citizens’ involvement can have positive and
lasting results.
Activity Notes and Troubleshooting
• Students may not be aware of their local natural ecosystems. Local maps and news
articles may help them identify a local ecosystem to investigate.
• Approve students’ ecosystem choices to be sure they are appropriate before students
begin significant research. In some cases, you may have to assist students in
identifying these areas. Sources of information might include the local public library
and local environmental groups.
• Consider planning a trip to a local conservation area or outdoor education centre.
• With students, decide on the audience they are targeting before they create the vehicle
to communicate their findings.
• Provide students with a rubric for the assessment criteria at the beginning of the
assignment.

TR-1-100 MHR • Unit 1 Sustainable Ecosystems 978-0-07-072367-2

Additional Support
• By using a generic rubric, you allow students to choose the medium that best suits
their particular ecosystem, audience, and preferred learning style.
• Be flexible in allowing students to speak about areas they are most familiar with. For
example, a student may want to address an area near his cottage or his grandparents’
home. You may decide to specify that the ecosystem must be from within Ontario, or
within Canada.
• ELL English language learners may find an activity that is so locally targeted
problematic. They should be allowed some flexibility. If they are very familiar with an
ecosystem within their country of origin, they may wish to address this area.
Rubric

ACHIEVEMENT
CHART Level 1 Level 2 Level 3 Level 4
CATEGORY

Knowledge & Human factors impacting Human factors impacting Human factors impacting Human factors impacting
Understanding the ecosystem are the ecosystem are the ecosystem are the ecosystem are
described in limited described in some detail. described in considerable described in thorough
detail. detail. detail.

Communication Includes information Includes information from Includes information from Includes information from
from a variety of sources a variety of sources using a variety of sources using a variety of sources using
using an accepted an accepted form of an accepted form of an accepted form of
form of academic academic documentation academic documentation academic documentation
documentation with with some effectiveness. with considerable with a high degree of
limited effectiveness. Communicates using effectiveness. effectiveness.
Communicates using scientific vocabulary with Communicates using Communicates using
scientific vocabulary with some effectiveness. scientific vocabulary scientific vocabulary
limited effectiveness. Communicates for the with considerable with a high degree of
Communicates for the chosen audience and effectiveness. effectiveness.
chosen audience and purpose with some Communicates for Communicates for the
purpose with limited effectiveness. the chosen audience chosen audience and
effectiveness. and purpose with purpose with a high
considerable degree of effectiveness.
effectiveness.

Application Analyzes information for Analyzes information for Analyzes information Analyzes information
bias and accuracy with bias and accuracy with for bias and accuracy for bias and accuracy
limited effectiveness. some effectiveness. with considerable with a high degree of
Analyzes information Analyzes information effectiveness. effectiveness.
to identify protection to identify protection Analyzes information Analyzes information
strategies and strategies and obstacles to identify protection to identify protection
obstacles with limited with some effectiveness. strategies and obstacles strategies and obstacles
effectiveness. Proposes courses with considerable with a high degree of
Proposes courses of action of some effectiveness. effectiveness.
of action of limited effectiveness. Proposes courses of Proposes highly effective
effectiveness. action of considerable courses of action.
effectiveness.

Please also see BLM A-45 Unit 1 An Issue to Analyze Rubric.

978-0-07-072367-2 Unit 1 Projects An Issue to Analyze • MHR 101

Unit 1 Review Answers (Student textbook pages 128 to 131)

Connect to the Big Ideas 7. Carbon dioxide has been increasing in the atmosphere
Connect to the Big Ideas answers are also available as a because we have been burning fossil fuels that release
Blackline master on the accompanying CD. carbon dioxide.
8. This example might be considered predation (bird preying
on insect parasite) or mutualism (bird benefits by getting
food, and large animal benefits by being rid of parasites).
Primary producers such as
plants and algae use photosynthesis 9. Urban sprawl is a form of development where houses and
to convert the Sun’s energy into
carbohydrates. They then use
cellular respiration to convert
business are built outside the core of the city, expanding
Life depends on the carbohydrates to
useable energy.
Populations have the city. These areas often have few services available,
recycled matter. a natural limit.
Processes include the They will increase making them car-centric.
water cycle, carbon cycle, exponentially until the
nitrogen cycle, and available resources
phosphorous cycle. cause them to reach 10. Organisms can be very small; they can be located in
their carrying
Ecosystems are dynamic
and have the ability to
capacity. places that we cannot access easily (for example, the
Keystone species
respond to change, within
limits, while maintaining theirEcosystem services are
ocean floor); they can have different life stages; they can
ecological balance.
affect the health of
the whole ecosystem.
the benefits experienced
by an organism provided
look similar but actually be different.
The decline of the sea by a sustainable
otter population caused
an increase in the sea
ecosystem. These services
include the provision of
11. any three of the following: Carolinian Canada of
urchin population, which
affected the kelp
clean water, cycling of
nutrients, pollination, and
southern Ontario, Leitrim Wetlands near Ottawa, Long
Certain species can
forest, causing a balancing growth and
loss of habitat
have a greater impact on
a community or an
decomposition. Point in Lake Erie, the Georgian Bay Biosphere Reserve
for fish.
ecosystem. The death of the
American Chestnut from a fungus 12. In the water cycle, water continually cycles through the
eventually caused the extinction
of seven insect species. hydrosphere, atmosphere, lithosphere, and biosphere
through the process of evaporation, condensation, and
precipitation. In the phosphorus cycle, phosphorus
moves through the hydrosphere, biosphere, and
lithosphere. It is carried from the lithosphere (soil) to the
hydrosphere (lakes and rivers) by water run-off.
Bioaccumulation is the increase of
toxins from one trophic level to another. Due
13. Plants are sometimes grown at a contaminated site to
Eutrifi- to the control and banning of substances
like DDT and PCB, we have seen
accumulate the poisons in their tissues, which cleans
cation is
populations of waterfowl and
caused by too much
phosphorous, mostly peregrine falcons recover
Ecotourism is
a benefit humans
many of the poisons out of the soil.
from fertilizer run-off. The since the 1970s. enjoy as a result of
Experimental Lakes Agreement ecosystem services. 14. Burning fossil fuels, such as gasoline in a car, increases
led to the Great Lakes Water Areas have been
Quality Agreement between
Canada and the United States.
protected to serve
as parks in order
the amount of carbon dioxide in the atmosphere, which
The phosphorous levels in Lake
Erie have decreased by over People have the
to preserve the
natural beauty.
travels with weather systems, and has a negative impact
50 percent since that time. responsibility to regulate
their impact on the sustainability on ecosystems far away.
Restoration Ecology is of ecosystems in order to preserve
them for future generations.
the renewal of destroyed
ecosystems through
By examining our own
ecological footprint,
15. Some energy in tertiary consumers is transferred
human intervention. The individuals can be
Don Valley Brick Works is motivated to alter their to a decomposer. Most is moved back to the abiotic
one example. What was once own behaviour instead of
a group of abandoned and trying to alter the carrying components of the ecosystem.
broken-down buildings is capacity of the planet.
Biodiversity hotspots are
now a naturalized
small areas that support a
area and
large number of species. In Thinking and Investigation
historical
Canada, some of these areas have
park.
been granted special status to protect 16. The ruby-throated hummingbird and the monarch
them from development. One such area is
Long Point Bay, now a World Biosphere butterfly migrate long distances every year, so they are
Reserve.
dependent on many ecosystems along their migratory
routes for food and shelter. Since these organisms rely
on many ecosystems, maintaining connectivity among
Knowledge and Understanding ecosystems allows them to survive, and also allows the
1. d. organisms that depend on them to survive.

2. d. 17. a. In the first graph, the number of bacteria is

increasing. In the second graph, the number of
3. a.
bacteria increased and then levelled off.
4. c. b. first graph
5. a. c. second graph
6. phosphorus d. yes, second graph

TR-1-102 MHR • Unit 1 Sustainable Ecosystems 978-0-07-072367-2

18. The carrying capacity is approximately 1.6 million. In Application
real life, populations can exceed the carrying capacity, 26. Questions might include the kinds and quantities of
but then they will run out of food. Once they number chemicals that were used; the likelihood of run-off;
less than the carrying capacity, their predators will run where and how the pesticide will be used and disposed
out of food and begin to die, allowing the population to of, what animals might come into contact with it, and
grow to exceed the carrying capacity again. how quickly it will decompose.
19. They harvest and hide seeds, some of which grow into 27. Answers should include an appreciation of the
new trees; stored seeds are a food source for other seed- importance and difficulties of sustaining several
eaters; squirrels are prey for larger predators like owls; ecosystems far apart and in different countries.
squirrels make nests that are later used by other small 28. Students should include a rationale for their course of
mammals; squirrels scold predators, warning other action, including risks and benefits; for example, using
animals. birds of prey to control the gull population does not
20. Acid precipitation causes forest soils to lose nutrients, introduce poisons into the environment, but birds of prey
and it also increases the amount of aluminum in soil, may eradicate other populations, and upset the balance
which interferes with the uptake of nutrients by trees. in the ecosystem.
Some species cannot survive these changes. Acid 29. Answers will vary, but sustainable activities use
precipitation also affects aquatic ecosystems because it resources more efficiently by using only what can be
can lower the pH of water, causing problems for fish, regrown. Unsustainable activities will eventually use
amphibians, and other organisms that live in the water. up the resource.
Some aquatic organisms are very sensitive to a drop
30. property in public ownership, proximity of industry
in pH.
that might imperil the restored wetland, proximity of
21. Canadians use more electricity; consume more oil; and residential development, size, links to other wild areas,
have more highways, which probably indicates more suitable topography
vehicle use.
31. It might cause you to spend more funding on foxsnakes
22. Answers will vary, but should include questions about because we have a greater responsibility for the global
chemicals and alien species that the ship may be population, and they have a smaller range overall.
carrying, and possibly also questions about where the
ship has been. Literacy Test Prep
Multiple Choice
Communication 32. b.
23. The greenhouse effect is the process in which greenhouse
33. b.
gases in the atmosphere—such as water vapour, carbon
dioxide, and methane—prevent heat from leaving the 34. d.
atmosphere, therefore increasing the temperature of 35. b.
the atmosphere. Without greenhouse gases, Earth’s
temperatures would be much colder than they are. Written Answer
36. CO2: Burning fossil fuels releases carbon dioxide into the
24. Answers may include symbols for biodiversity,
atmosphere. It is believed that increased carbon dioxide
communities, environmental groups, traditional is causing global warming.
ecological knowledge, and stewardship. Alternatively,
symbols may represent five different rich ecosystems, for vehicles driven: Vehicle emissions contribute to acid
example, aquatic, tundra, prairie, forest, and wetland. precipitation.

25. Flowcharts should show many of these connections: paper used: Cutting down trees to produce paper leads to
erosion, a loss of habitat, and less photosynthesis.
• Prairie dogs → “dog towns” (burrow system) → poisoned,
trapped, shot → soil poor, drier, plant diversity drops gasoline used: Gasoline is a fossil fuel that when burned,
• prairie dogs → “dog towns” → prairie rattlesnake, black- releases carbon dioxide into the atmosphere.
footed ferrets use the burrows and eat the prairie dogs → fresh water used: Water sources can dry out during long,
population reduced hot periods with no rain. Chemicals from industries can
• captive breeding in zoos → trained for wild → contaminate water.
re-introduced → population rescued Sustainable practices may vary, but should address the
issues listed above.

978-0-07-072367-2 Unit 1 Review • MHR TR-1-103