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CONCEPT OF ECOLOGY
Facilitators;
Makeo Onani & Ayeko Daniel
Department of Biology
St. Joseph of Nazareth High School- Kavule

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Competency Learning outcomes

The learner understands the concepts of communities, habitats,
and ecosystems.
You should be able to:
• know the meaning of the term ecology (k)
• understand the concepts of communities, habitats and
ecosystems (s, u)

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Introduction
Key words Ecology is a branch of biology that deals with the relations of
organisms to one another and to their physical environment.
Living and non-living things exist in the same environment. Many
• Ecosystem • Marine • Secondary living things benefit from each other, from non-living things as
• Ecology • Forest consumer well as the environment. The interaction between various living
• Tertiary consumer things around is important because it ensures our survival and
• Autecology • Population the survival of other organisms.
• Synecology • Aquatic • Quaternary
There are two types of ecology that’s to say , autecology, which
consumer deals with the study of individual species of plants and animals
• Habitat • Arboreal
and synecology which deals with the study of communities
• Community • Terrestrial (plants and animals under similar conditions).
• Environment • Producer Ecological studies therefore, will provide learners with an
• Estuarine • Primary consumer excellent opportunity to demonstrate the link between plants and
animals and their interdependence.
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• Ecology
TERMINOLOGIES USED IN ECOLOGY
• Biosphere
• Ecological niche
Activity (a): Understanding the terms used in ecology
Leading question: • Species
What is the meaning of the different concepts in ecology? • Environment
Materials • Population
Textbooks, Ecological journals, Internet, Dictionary • Habitat
In groups • Ecosystem
1. Discuss, describe and note down any five components of the • Community
environment.
3. Present your findings to the rest of the class members for
2. Research the meanings of the following terms as used in discussion.
biology.
4. Make notes from the presentation.
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The environment is made up of living organisms that interact with BIOSPHERE

each other and the non-living environment around them. In the
study of ecology, the following concepts are very important
because they form the basics of understanding the topic.

(a) Biosphere: This is the part of the earth surface and

atmosphere where living organisms are found. (where life
exists). Examples include , from the root system of the trees,
to the dark environments of ocean trenches, forests,
mountains, lakes e.t.c

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(b) Ecological niche (c) Species

In ecology, a niche is the match of a species to a specific A group of similar organisms capable of interbreeding to produce
environmental condition. It describes the role an organism plays reproductively-viable offspring. For example , lions are a species
in a community. For example, the ecological niche of a wood because they are capable of reproducing viable offspring upon
pecker on a tree as its habitat, is the tree hole where it nests. interbreeding

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(d) Population (e) Community

A community is a group of two or more species(populations)
occupying the same area(habitat) at the same time and
This refers to all individual members of a particular species interacting together. This includes all plant and animal species
occupying same habitat at a given time. For example, the found in the same habitat. For example , a forest has trees,
population of lions in queen Elizabeth national park is 250. monkeys , leopards, birds, bees,

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(f) Ecosystem (h) Habitat

This is a unit of the environment consisting of both living and non It is the specific area in the environment with a certain set of
living components interacting with each other in forming a self- conditions where an organism lives. The environment offers food
sustaining unit. For example, the tropical forest is an ecosystem ,shelter, protection and mates for reproduction. It is made of
made up of living organisms such as trees, animals, insects and living components referred to as biotic factors and non living
micro-organisms that are in constant interaction with each other factors called abiotic factors. Examples of biotic factors are;
and with their physical environment like ponds, forests , rocks, plants and animals. Examples of abiotic factors include
light to form a self sustaining unit. temperature, light, soil texture, topography, atmospheric
pressure, pH, salinity, humidity and mineral elements in the soil.
The four main habitats are aquatic ,estuarine, terrestrial and
arboreal.

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MAIN ECOSYTEMS FOUND IN EAST AFRICA

Activity (b): Identifying communities, habitats and ecosystems in East
Africa.
Key question: What are the major ecosystems found in East Africa?
In groups:
1. Study the map of east Africa showing settlement of communities
and its physical features.
• Identify at least five ecosystems
• State their distinguishing features/characteristics.
2. Make a write up describing the ecosystems of East Africa and their
characteristic.
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MAP OF EAST AFRICA The five main ecosystems in Africa are: savanna grasslands,
marine or coastal ecosystems, fresh water ecosystems, tropical
rain forests and semi arid ecosystems.

Physical features with their major characteristics

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Main physical feature Major ecosystems Distinguishing features Aquatic Fresh water ecosystem • Consists of lakes, rivers, swamps, ponds etc.
• Contain fresh water with low salt content, the
water is either slow moving, fast moving or
Mountains Tropical rain forests • Consist of mainly tropical and sub-tropical
stagnant
ecosystem rain forests
• Have lower temperatures compared to the
• Contain more of diverse flora and fauna
terrestrial ecosystem
• They are warm and moist through out the
• Temperatures are usually stable throughout the
year
• Light intensity and penetration decrease with
• Consist of tall trees with dense foliage
increase in depth.
• Species habitats from the forest floor to
canopy

Oceans and seas Marine ecosystem • Consists of oceans in east Africa

Plains Savanna grasslands • Composed of savanna vegetation • Contains salty water
• Grasses are most abundant here • Have lower temperatures compared to the
• Have scattered trees and shrubs terrestrial ecosystem
• Consist of dry and rainy seasons • Temperatures are usually stable throughout the
• Have herds of grazing animals day
• Warm throughout the year • Light intensity and penetration decrease with
increase in depth.
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Activity (c): Identifying different ecosystems and their

Deserts /semi-arid Semi-arid/desert ecosystem • Receive little or no rainfall characteristics.
• Have high temperatures
during the day and cold Key question: What are characteristics of different ecosystems?
temperatures at night
• Consists of sparse
1. Compile a list of ecosystems you know , with their
vegetation characteristics.
• Have sand dunes and oases 2. State the ecosystem where the following organisms live;
(a) Fish
(b) Monkeys
3. Describe how these organisms are adapted to living in their
respective ecosystems mentioned.

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Discussion 1
Tropical rainforest ecosystem
Tropical rainforest ecosystems
These are large tracks of land covered by trees.
Characteristics
• High humidity due to high rainfall throughout the year
• Contains more diverse flora and fauna
• Consists of tall trees with dense foliage
• Species in habitat from forest floor to canopy.
• Forest canopy and floor have varied light penetration.
• Are main sources of rivers hence characterized by numerous
streams and water ponds.

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Savanna grassland ecosystems

These are open grasslands that occupy extensive areas in East Africa ,
especially Kenya, Tanzania, and some areas in Uganda. Savannas have
been set aside as habitats for wildlife. They are also home for mixed
pastoral or nomadic communities.

Characteristics
• Occupy flat rocky surfaces with black cotton soils
• Have tall grasses with scattered trees or shrubs (xerophytic vegetation)
• Animals found in this ecosystem include grazers like zebras, kobs, and
predators like lions and leopards
• There are high rates of evapo-transpiration and periodic severe drought
• Strong winds are felt periodically
• Unpredictable rainfall is always received which is poorly distributed
annually.

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Semi-arid/desert ecosystem

Semi-arid/desert ecosystems Semi-arid/desert ecosystem

Semi-arid/desert ecosystem cont’d

These are areas in the leeward side of the mountains. In • Plants found here include; cactus, small tuffs of grass and
Uganda, they include areas in Karamoja and Teso. shrubs like acacia. Plants like cactus have needle-like leaves
Characteristics and succulent stems. Shrubs have thorns on them while other
• Receive very low rain that is poorly distributed annually or no plants have small leaves. Most of the plants have long and
rainfall may be received. deep roots to seek water from below the surface.
• Soil is composed of rocks, rock fragments and sand. • Animals found here include camels and reptiles such as
alligators , snakes and dragon lizards. They have tissues that
• Seasonal rivers and oases provide water to the organisms living
are tolerant to heat and dehydration.
there.
• Have extremely high temperatures during the day and cold
temperatures.

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Marine ecosystems
These are areas around the oceans, seas and major salt lakes like
Katwe and Bunyampakwa in Uganda, Nakuru in Kenya among others.
The salty lakes are inland waters that are alkaline.
Characteristics
• Oceans and seas have salty water. The soils in this ecosystem are
also salty
• Have lower temperatures compared to the terrestrial ecosystem.
• Temperatures are usually stable throughout the day.
• Light intensity and penetration decrease with increase in depth.
• There are various plants that are tolerant to salty waters in the lakes.
Animal species include marine fish, flamingoes and invertebrates.

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Fresh water ecosystems

These include lakes, ponds, rivers, streams, springs and wetlands(swampy
areas). Fresh water ecosystems can be divided into still water and flowing
water.
Characteristics
• Contains fresh water with low salt content, water is either slow moving, fast
moving or stagnant.
• Wetlands and banks of lakes and rivers have waterlogged soils.
• Plants that grow in this ecosystem type are hydrophytes; with broad flat
leaves and others straw-like leaves.
• Have lower temperatures compared to the terrestrial ecosystem.
• Light intensity and penetration decrease with increase in depth.
• There are many animal species ranging from hippopotamus, crocodiles,
frogs, fishes, and eels.

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Discussion 2

Organism and its ecosystems

• Fish – fresh water ecosystem
• Monkeys - forest ecosystem
Adaptations of each organism to the ecosystem they live in;
Fish
 Have gills that allow them to carry out gaseous exchange
 Have a stream lined body which reduces water resistance when
they swim.
 Fish have several fins used for swimming and balancing in water.
Most fish have a swim bladder, this enables the fish to move up and
down while in water by changing the amount of gas in the swim
bladder.

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Adaptations of monkeys to their ecosystem. COMPONENTS OF AN ECOSYSTEM

 Have a strong tail that can grab and hold supports. Activity: Investigating components of an ecosystem.
 have lungs for gaseous exchange, since forests are found in Key inquiry: What are the main components of an ecosystem?
the terrestrial environment. Requirements:
Make use of sound to locate one another, in the dense forests A local ecosystem; for example pond , river , lake, forest, arid
where vision is hard. area.
Have powerful hands and fingers that are able to grasp around Note book.
tree branches. In groups:
Have fur to protect excess heat loss and keep them warm in 1. Visit an ecosystem that is closest to your school. (school
the usual low temperatures in the forest ecosystem. pond)
2. Study the biotic and abiotic factors in that particular
ecosystem.

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Brain storm in your groups and then do the following:

Discussion:
a) Make a list of all the biotic and abiotic components of the
Components of an ecosystem are broadly categorized as
ecosystem.
biotic(living) and abiotic (non-living). Examples of abiotic
b) Make a list of individual populations of species living in the components in an ecosystem include;
ecosystem.
__________________________________________________________
c) Make a list a various communities of organisms living in the __________________________________________________________
ecosystem.
__________________________________________________________
d) From the communities that you have identified, suggest the __________________________________________________________
dominant species and give reasons for your answer. __________________________________________________________
e) Make a report and present to the class. __________________________________________________________
f) Summarise the presentations individually in your notebooks. __________________________________________________________
__________________________________________________________

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Examples of biotic factors are as follows

Study on the school pond;
Plants like trees, grass, papyrus, water hyacinth and water lilies.
Animals like human beings, The dominant organisms in this ecosystem are
_______________,__________________ ………………………. and plants around the pond . Fish are the
_______________________; ___________________; _____________; dominant animal because they provide food for the human
beings, fish eating birds, water ducks , water snakes.
among others.

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The habitats within this ecosystem are;

The communities found there are as follows;

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INTERACTION OF ECOSYSTEM COMPONENTS

Green plants and algae use sunlight energy, water and carbon
dioxide to make food (photosynthesis) , which provides the
energy needed by all organisms to grow and live.
Research question:
In groups, describe how the abiotic factors and abiotic factors
interact in the ecosystem to maintain a self sustaining system.

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FOOD CHAINS AND FOOD WEBS

Competency:
The learner appreciates the interdependence of organisms in a
given ecosystem.

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Learning outcomes Key words

 Energy  Consumer
The learner should be able to:  Biomass  Decomposer
• understand the feeding relationships in an ecosystem, and  Food chain  Scavenger
express them using food chains, webs, and pyramids (k, u, s)  Food web  Trophic level
• appreciate the organisms and processes involved in the carbon  Photosynthesis  Carbon cycle
cycle, and its role in maintaining the carbon dioxide balance in  Producer  Respiration
the atmosphere (u, v)
 Pyramid

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INTRODUCTION: FEEDING RELATIONSHIP IN AN ECOSYSTEM

As earlier discussed, an ecosystem has both living components Feeding relationships in an ecosystem can be expressed in two
and non-living components. The living components depend on ways, that is either using the food chains or food webs.
non-living components and the latter on the former. When living
things benefit from each other, they form a chain of dependency
which results in a food chain.

Basically, all animals depend on plants for their food either

directly or indirectly.

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Study figure and identify which organism feeds on the other and fill in the
Activity(a): Understanding the difference between food chain and blank spaces. (Pg 122 Active Biology Students’ Book 4)
food web.
Key question: What is the difference between food chain and
food web?

In groups

1. Distinguish between food chain and food web.

2. The following photographs were taken by senior four learners

when they visited a game reserve.

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Organism(s) Eaten by
(i)........... is eaten by ...........
(ii).......... is eaten by ..................... which is eaten by ...........
(iii)......... is eaten by ....... is eaten by .......... is eaten by ........

3. From your response in 2 , replace the phrase “is eaten by”

with an arrow and construct a food chain. Include more
possible food chains.

4. Give the alternative food sources and choose an organism

that is eaten by two or more organisms. Fill the table below.
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Discussion:
A food web:
1. Difference between food chain and food web.
• A food chain is a sequence of feeding relationships from the
Is a complex nutritional relationship showing alternative sources
producers to the consumers. A food chain is a simplified sequence of of food for each organism in a community. The food web
transfer of matter and energy in the form of food from one organism to consists of a number of interlinked food chains. It gives a clearer
another in a community. Food chains are linear and tend to show only picture of what occurs in a community than the food chain that
one source of food for an individual organism represented. provides no alternative source of food.
• For example, considering a feeding relationship between grass,
grasshoppers, a dove and cat.
• The grasshoppers feed on grass which is a producer, hence
grasshoppers are primary consumers on grass. The dove feeds on
grasshoppers which qualifies it to be a secondary consumer. Then
finally, an animal such as a cat feeds on meat from the dove hence
being a tertiary consumer.
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Illustration of food chain and food web Responses

2.
Identity of which organism feeds on the other.
(i)Grass is eaten by zebra
(ii)Grass is eaten by zebra which is eaten by lion.
(iii)Grass is eaten by zebra which is eaten by lion is eaten by
crocodile.

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NB:
3. Food chains
 Each food chain starts with a producer and the food then
passes on to a primary consumer, next to a secondary
consumer and so on.
 The arrows represent the transfer of food between the trophic level.
 The food chain is open ended and each individual has only one
source of food thus no alternative.
 The number of links (producers and consumers) in a food
chain may vary, but does not usually go above five.
 Arrows used are eaten by arrows i.e it goes from the eaten
individual to the predator.

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4. Give the alternative food sources and choose an organism that Sample food web of the organisms in discussion
is eaten by two or more organisms. Fill the table below.

Organism(s) Eaten by Draw the food in your groups and present it on a manila
paper.
Plants Zebras, impalas, elephants,
buffalos, rhinos.
Zebras, impalas, Cheetahs and lions
elephants, buffalos, rhinos.
Zebras, impalas, buffalos, Crocodiles
rhinos, Cheetahs and lions
Zebras, impalas, buffalos, Hyenas and marabou storks
rhinos, Cheetahs and lions
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NB:
 A food web is an interlinked multiple food chains of all the
organisms given in the list above.
 Organisms are grouped as producers, primary consumers,
secondary consumers and tertiary consumers.
 Arrows connect showing the transfer of energy from one
organism (the source of food- Guinea grass/ maize plant) to
another (the predator).
 Arrows represent the transfer of food between the trophic level.

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Exercise
Responses
1. Study the organisms in the table below, to construct possible 1. Sample food chains for the organisms give
food chains. ................................................................................................................
................................................................................................................
Guinea grass, Lizard, Grasshopper, Hen, Hawk, ................................................................................................................
Termite, Frog, Heron, Antelope, Lion, Vulture, Maize ................................................................................................................
plant ................................................................................................................

2. Sample food web for the organisms give

1. Use the constructed food chains in activity (a) above to ................................................................................................................
develop a food web. ................................................................................................................
................................................................................................................
2. Make a summary of the presentations in your notebook. ................................................................................................................
................................................................................................................

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Elimination of one trophic level in a food chain, causes changes

in numbers of individual at other trophic levels and may ultimately Discussion
lead to total collapse of the food chain. 1. The population of the primary consumers gradually decreases
and eventually disappears due to starvation.
Thought 2. The populations of the secondary and tertiary consumers also
(a) What happens when all the producers (plants) are removed decrease up to extinction.
from the food chain? 3. The population of the decomposers increases due to a lot of
organic matter present in the environment.
4. The amount of oxygen in environment decreases due to
decomposition and a lot of carbon dioxide is released into the
environment and not removed by the producers for
photosynthesis.
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(b) What happens when the secondary consumers are eliminated

from the food chain?
Conclusion
1. The population of the primary consumers increases greatly for
Basing on the above explanation, you should know that there is need
a while, later they start competing and gradually reduce.
to for strengthen measures against activities such as deforestation,
2. The population of the producers decreases due to over
poaching, use of insecticides, bush burning, swamp reclamation, etc.,
consumption by the increased number of primary consumers.
which tend to eliminate both habitats and organisms from the
3. The population of the tertiary consumers decreases gradually environment thus breaking food chains. This will ensure both
and eventually disappears due to starvation. environmental conservation and sustainability of the ecosystem
through completion of food chains and webs.

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ECOLOGICAL PYRAMIDS What is pyramid of numbers?

These are histograms that provide information about the number of
Pyramid of numbers: It is a histogram representing the total numbers
individuals, biomass and amount of energy at each feeding (trophic) of organisms at each trophic level in the food chain of an ecosystem at
level in an ecosystem. any one time. It follows the energy flow pattern from producers to the
top consumer or carnival.
Ecological pyramids give a clearer picture of what happens in a
community as it gives the number of individuals, biomass and amount How to construct a pyramid of numbers.
of energy at each trophic level unlike the food chains and the food
1. Count the number of organisms at each trophic level, that is
webs. producers, primary consumers, secondary consumers and finally
Types of ecological pyramids tertiary consumers.
2. Using rectangles, in which each rectangle represents the number of
1. Pyramid of numbers organisms at each trophic level, draw a pyramid with producers at
2. Pyramid of biomass the base, followed by primary consumers, secondary consumers
and finally tertiary consumers as shown in the figure below.
3. Pyramid of energy

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Note: Activity (b) : Constructing a pyramid of numbers using data from a field
study.
The length (or area) of a rectangle represents how many Key question: How would you construct would you construct a pyramid
of numbers using data using data collected from a field study?
organisms they are at each particular trophic level. For example,
the size of the rectangles in the pyramid decreases as you move
In groups
from producers to tertiary consumers. 1. Conduct a field study in a selected area (ecosystem) to identify the
organisms that live there.
The number of organisms also decrease at each trophic level as 2. Record the number of organisms identified belonging to each
you move up the pyramid, but the size of each individual trophic level. In groups, use the data to obtain to construct a
increases. pyramid of numbers.
3. During a field study in the savanna grassland, the following
numbers of organisms was recorded.

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Organisms Number (a)Show the numbers of organisms at each trophic level when
Grass/ 50,000 they were added together.
vegetation hectares (b)Use the information above to develop a food chain and
Buffalos 3,000 pyramid of numbers.
Impalas 10,000 (c)Explain the appearance of pyramid of numbers.
Elephants 1,000
Rhinos 300
Share your findings with the rest of the class.
Cheetahs 300
Crocodiles 400
Lions 300
Hyenas 150
Marabou stork 50
Vultures 50
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Discussion Food chain

The numbers of organisms at each trophic level when they were
added together.
Construct a food chain from the above table
Producers Primary Secondary Tertiary Quaternary
consumers consumers consumers consumers

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Pyramid of numbers General pyramid of numbers

Draw a pyramid of numbers for any of the above food chains

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1. Pyramid of biomass:
Explaining the appearance of pyramid of numbers. • It is a histogram showing the total dry mass of organisms
present at each trophic level. These convey more information,
- The size of the rectangle represents how many organisms exist since they consider the total mass of living organisms at each
at each trophic level. For example, the size of the rectangles in trophic level. The biomass of producers is greater than biomass
the pyramid decreases as you move from producers to tertiary of primary consumers and so on.
consumers. • The biomass decreases from each trophic level to the next in
- The number of organisms also decrease as well at each most cases and the biomass should be dry mass (since water
trophic level as you move up the pyramid. stores no energy) and is measured in kg m-2. The biomass may
be found by drying and weighing the organisms at each trophic
level, or by counting them and multiplying by an average
individual mass.

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Pyramid of biomass Disadvantages of the pyramid of biomass

• The biomass of an individual can vary during the year due to

environmental changes.
• Some organisms grow at a much faster rate than others and so
do not have a large biomass.

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1. Pyramids of Energy ILLUSTRATION OF PYRAMID OF ENERGY

Pyramids of energy shows how much energy flows into each

trophic level at a given time. The flow of energy in an ecosystem
is unidirectional since energy does not go back to the sun the
main source. From each energy level, energy goes on reducing
hence the pyramid of energy is always upright. From the food
chain normally energy is lost in form of heat. This is the most
accurate ecological pyramid.

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• From the primary consumers, energy then flows to the

ENERGY FLOW IN AN ECOSYSTEM.
secondary consumers which obtain about 10% of the energy
• The sun is the main source of energy in the ecosystem. Energy enters the from the primary consumers, the 90% is lost as heat, used for
food chain when photosynthetic organisms called producers [plants, algae, growth, and some remains in indigestible parts like bones,
and phytoplankton] trap sunlight to manufacture food by photosynthesis. hooves, hair and skin. The trend is maintained even as tertiary
Only about 10% of the sun’s energy is used by the producers to make food consumers feed on secondary consumers. Decomposers
(biomass) and the rest is lost as; it is reflected by the clouds or on surface of
plants and also some radiations fall on non-photosynthetic surfaces like bare
however take in only 1% of the energy from dead bodies thus get
land. the least amount of energy.
• From the producers, energy then flows to the Primary consumers which • The amount of energy decreases at each successive
take in only about 10% of the energy in producers, the rest (90%) of the feeding/trophic level because of the great energy losses, so the
energy is lost as heat, some remains locked up in indigestible parts of the energy left in organisms is little to support large numbers at top
plant like cellulose and some is used for growth [cell division]. consumer level. The energy flow is noncyclic since energy does
not flow to the sun where it comes from.
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CYCLING OF MATERIALS
• Carbon cycle describes the process in which carbon in the form
of carbon dioxide and organic carbon is interchanged between
living and non-living components of the atmosphere to keep
concentration of carbon dioxide in balance.
• The carbon cycle is a biochemical cycle by which carbon is
exchanged among the biosphere. It involves processes like
photosynthesis, respiration and combustion, some of which are
controlled by bacteria. Carbon dioxide imbalance in recent times
has resulted in global warming a situation where the temperature
of the earth and its atmosphere has increased, affecting seasons
and life.

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Activity(c): Understanding and appreciating the importance of carbon

cycle in the biosphere. Video to watch
Key inquiry : How can you represent carbon cycle diagrammatically?
In groups
1. Watch a video clip showing how carbon cycle takes place in the
biosphere. Note the key stages of the carbon cycle.
2. Draw a diagram representing how carbon cycle takes place in the
biosphere.
3. Tell the organisms and processes involved in the carbon cycle.
4. Explain the role of the cycle in maintaining the carbon dioxide
balance in the atmosphere.

Present your findings to the rest of the class.

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Discussion:
Key stages involved in the carbon cycle in biosphere.

- Carbon enters the atmosphere as carbon dioxide.

- Carbon dioxide is absorbed by autotrophs such as green
plants.
- Animals consume plants, thereby, incorporating carbon into
their system.
- Animals and plants die, their bodies decompose and carbon is
reabsorbed back into the atmosphere. OR. Burning of carbon
containing substances also adds carbon into the atmosphere.

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Diagram showing how the carbon cycle takes place in the

biosphere.
Schematic drawing of the carbon cycle

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Organisms and processes involved in the carbon cycle and their Microorganisms (such as fungi and bacteria):
roles.
These return carbon to the environment when they decompose
Plants: These absorb carbon from the environment during
dead plants and animals. Carbon in inedible parts of plants can
photosynthesis and release it back during respiration.
be released back into the atmosphere through: decomposers
Animals: These obtain their carbon by eating plants and animals breaking down the inedible parts of dead plants, thus returning
and release carbon in form of carbon dioxide into the atmosphere the carbon in their bodies to the atmosphere as carbon dioxide
during respiration. by respiration.
The plant and animal materials may then be available as fossil
fuels for combustion in the future.

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 6/5/2024

Basing on the findings from the activity, the carbon cycle is

essential in maintaining the carbon dioxide balance. You have
also realized that that there are various processes such as
photosynthesis, respiration, decomposition and combustion
through which carbon dioxide through which the organisms
obtain carbon dioxide from the environment and also releases
the excess of it into the atmosphere. To God be the glory…

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