KZN Step Ahead Life Sciences Grade 11 learner Support Document January 2021

STEP AHEAD

LEARNER SUPPORT DOCUMENT

GRADE 11

LIFE SCIENCES
JANUARY 2021

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KZN Step Ahead Life Sciences Grade 11 learner Support Document January 2021

NO. TOPIC PAGE

1. Classification of Micro-organisms 3----7
2. Plant Diversity 8-----14
3. Animal Diversity 15-------25
4. Photosynthesis 26------40
5. Animal nutrition 41-------49
6. Cellular respiration 50-----52
7 Gas exchange 53------60
8. Excretion in man 61------73
9. Population ecology 74------81
10. Human impact on environment 82--------90

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D. CLASSWORK/HOMEWORK

Activity 1 (Viruses)

1.1 The diagram below represents the structure of a Bacteriophage.

1.1.1 Identify the following parts:

(a) A
(b) B
(c) C
(d) D 4
1.1.2 Why are viruses referred to as being acellular? 1
1.1.3 State ONE characteristic of viruses that qualifies them as:
i. Living things
ii. Non-living things
2
1.1.4 Predict what would happen if a virus cannot find another living cell. 2

Activity 2 (Viruses)

2.1 AIDS is a human disease caused by a virus. Viruses are referred

to as obligate parasites.

2.1.1 What does AIDS stand for? 1

2.1.2 Name the pathogen that causes AIDS 1
2.1.3 Why are viruses referred to as being obligate parasites? 1
2.1.4 Describe the effects of drug abuse on the spread of HIV. 4

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2.2 Briefly describe how a virus multiplies inside a host cell. 6

(13)
Activity 3 (Bacteria)

3.1 Explain why bacteria are regarded as:

3.1.1 Autotrophic 1
3.1.2 Heterotrophic 1
3.1.3 prokaryotic 1

3.2 For each of the phrases in column 1, state whether it applies to A

only, B only, Both A and B or none in Column 2. Write down A
only, B only, Both A and B or None in your answer book.

Column 1 Column 2
3.2.1 Presence of a protein capsule and a A. Viruses
well- defined nucleus B. Bacteria
3.2.2 Not well-defined nucleus present A. Viruses
B. bacteria
3.2.3 May cause disease A. viruses
B. bacteria
3.2.4 Can occur as autotrophs, saprotrophs A. bacteria
or B. viruses
parasites
3.2.5 Considered non-living A. bacteria 10
B. viruses (13)

5x2

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Activity 4 ( Protists: malaria)

4 Study the extract below about malaria

4.1.1 To which group of micro-organisms does the malaria parasite belong? 1

4.1.2 State TWO ways to avoid contracting malaria 2

4.2 4.2.1 Describe how the malaria parasite is passed from one human to
another 2
4.2.2 Give ONE reason why a person with malaria cannot be treated by
using an antibiotic 2
4.2.3 Explain how an increase in the number of malaria infections would
affect the South African economy.
2
Suggest ONE way in which the data about the number infections was
4.2.4
collected.
Give ONE reason why the number of infections might have been more 1
4.2.5 than 7000 in year 2015
1
(11)

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Activity 5 – Classwork –

(Summary table on comparison of micro-organisms)

5 The table below summarises the diversity of micro-organisms. Complete

the table under each appropriate column

Characteristic

Organism Kingdom Type of cell Mode Mode of

nutrition reproduction

Viruses No Kingdom 5.1…………. 5.2……………. Inside a host

cell

Bacteria 5.3………….. 5.4…………. 5.5……………. 5.6……………

Protists 5.7…………. 5.8…………. 5.9……………. 5.10…………..

Fungi 5.11…………. 5.12………… 5.13…………. 5.14…………..

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Activity 6: Immunity (Vaccines)

6.

6.1 Name the substances that are produced by the body, which destroy
harmful viruses and bacteria. 1
Why does method A give long-lasting protection against Polio?
6.2 1
Method B does not give long-lasting protection against tetanus, why?
6.3 1
In immunisation against polio, a second dose of the weakened virus is
6.4
given (known as a booster). Suggest why this booster is necessary
1
Why is method B very good for dealing quickly with an infection like
6.5 tetanus?
1

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(5)

Topic: PLANT DIVERSITY

D. CLASSWORK/HOMEWORK Activity 1

1.1 Study the diagram below showing the structure of a moss plant
and answer the questions that follow.

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1.1.1 Name the parts labelled:

(a) 1 (1)
(b) 2 (1)
(c) 3 (1)
1.1.2 Which generations is represented by:
(a) A (1)
(a) B (1)
1.1.3 Give the letter and the name of part which is haploid (1)
(6)

1.2 Study the diagram, which shows the alternation of generations

and answer the questions that follow.

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1.2.1 Complete the missing terms on the diagram. (4)

(a) 1
(b) 3
(c) 4
1.2.2 Which process in plants cells will:
(a) Increase and (1)
(b) Decrease the chromosome number? (1)
(5)

Activity 2

2.1 Study the two plants A and B from different groups and answer the
questions that follow.

2.1.1 Study the two plants A and B from different groups and answer the (2)
questions that follow.

2.1.2 Name the reproductive structures formed inside the part numbered 1 (1)
2.1.3 Is the gametophyte generation of these plants haploid or diploid? (1)
2.1.4 Which plant (A or B) is a thallus? (1)
2.15 Explain why the plant identified in QUESTION 3.3.4 is a thallus. (1)
(6)
Activity 3

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3.1 The diagrams below shows plants from different divisions of the plant
kingdom.

3.1.1 Name the division to which plants I and II belong, respectively. (2)
3.1.2 State TWO differences between plants I and IV with reference to (4)
reproduction.
3.1.3 State only the NUMBER of the plant group which has no vascular (1)
tissue.
3.1.4 Place the plants in the correct sequence from primitive to most (2)
advanced.
(9)
Activity 4

4.1 Study the phylogenetic tree below, taking note of how the four plant
divisions have evolved and answer the questions that follow.

4.1.1 What us the ancestral form of all the plant divisions shown? (1)
4.1.2 Which plant division is the best adapted to life on land? (1)
4.1.3 Which plants are the most closely related? (2)

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4.2 The diagram below is a cladogram showing the evolution of

various plant phyla.

4.2.1 Identify the plant division labelled A,B,C and D. (4)

4.2.2 Name the evolutionary features at W and X , respectively, that
distinguishes:
(a) Mosses and ferns (1)
(b) Cone-bearing plants and flowering plants (1)
4.2.3 Both cone bearing plants and flowering plants are seed-bearing
plants. What is the collective term used for all seed-bearing plants? (1)

(7)
Activity 5

5.1 Flowers are reproductive structures used for sexual reproduction in

angiosperm plants. Study the diagram below and answer the
questions that follow.

5.1.1 Is this flower insect, wind ,or bird pollinated? (1)

5.1.2 List THREE characteristics of this flower that makes it well adapted (3)
for your answer given in question 7.1.1
(4)

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5.2 Study the diagram of a flower of an Angiosperm and answer the

questions that follow.

5.2.1 Write down the number of the part where the female gametes would (1)
be produced.
5.2.2 Which number represents the whorl that is important for insect (1)
pollination?
5.2.3 On this flower, both male and female organs mature at the same (1)
time. Mention ONE observable feature that helps to prevent self-
pollination.
5.2.4 State ONE way in which the Angiosperm is better adapted to a (2)
terrestrial life than the Bryophytes.
(5)
Activity 6

6.1 Study DIGRAMS 1 and 2 of angiosperm flowers below and

answer the questions that follow.

6.1.1 Provide labels for structures A to D. (4)

6.1.2 Give the letter of the structure where the seed is formed. (1)
6.1.3 Neither of these flowers is wind pollinated. Give TWO ways that (2)
you would identify a wind pollinated flower.
6.1.4 Give TWO advantages of sexual reproduction. (2)
6.1.5 State TWO ways in which the Angiosperms are better adapted to (2) (11)
a terrestrial life than Bryophytes.

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6.2 Study the diagram below showing the structure of a flower.

6.2.1 What type of pollination can be linked to this flower? (1)

6.2.2 Identify the parts labelled 1 and 2. (2)
6.2.3 What do we call 5 and 6 together? (1)
6.2.4 Using the NUMBER only, identify the following:
(a) Part which receives pollen (1)
(b) Structure where a seed can form (1)
(6)
Activity 7

7.1 Read the article below and answer the questions that follow.

7.1.1 What are suitable conditions for keeping seeds in a seed bank, (1)
according to the article?
7.1.2 What environmental event is threatening the safety of the seeds at (1)
the Global Seed Vault?
7.1.3 Give THREE different ways in which seeds provide a source of food (3)
for humans.
7.1.4 Why are seed banks important for the future? (2)
(7)

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7.2 The purpose of SGVSV is to store seeds for use 50 or more years
from now. Seeds from these three varieties of maize were tested to
see the effects of long term storage.

7.2.1 Explain how SGSV could generate these results (2)

7.2.2 Which variety of seeds are best suited for long term storage (1)
7.2.3 Determine the percentage of variety B seeds that would be still viable (2)
after being stored for 40 years.
7.2.4 A farmer sows 2100 seeds of variety A which have been stored for 35 (3)
years. Calculate the number of seedling that the farmer should
expect.
7.2.5 State a hypothesis for this investigation (2)
7.2.6 Identify the following variables:
(a) Independent (1)
(b) Dependant (1)
[12]

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Topic: Animal Diversity

Activity on symmetry

Teaching tool 2

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ACTIVITY

Fill in the biological terms on the blank spaces

NO. Description Biological Term

1. Body wall consisting of two germ layers

2. A gut with only one opening, used for both ingestion

3. The concentration of sense organs into the anterior part

of an organism to form a ‘head’ region

4. The arrangement of body parts such that an organism can

be divided into identical parts vertically along any radius

5. A gut having two openings, one for ingestion and one for
egestion

6. Body wall consisting of three germ layers

7. The arrangement of body parts such that an organism

can be divided into identical parts in only one way through
the midlongitudinal line

8. Blood system in which blood flows from the blood vessels

into open spaces
9. The germ layer giving rise to cells form the muscles and
other internal organs in the body

10. Type of symmetry relating to organisms that have an

irregular shape and can thus not be divided into two
identical parts

11. A true body cavity that is lined on both sides by

mesoderm
12. Blood system in which the blood is always confined to
the blood vessels

13. The germ layer that gives rise to cells that line the gut

14. A body cavity that is line by mesoderm on one side only

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D. CLASSWORK/HOMEWORK

Activity1 PCT: June 2014 - 3.3

Study the diagram representing two animals and answer the questions that follow.

A B

1.1. Identify the phylum in which organism A belongs (1)

1.2. State the type of symmetry of animal B? (1)

1.3 State whether each of organisms A and B are diploblastic or triploblastic. (2)

1.4 Explain how the body plan of the following organisms relate
to their mode of live

(i) Organism A (3)

(ii) Organism B (3)

(11)

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Activity 2

2.1. Write the LETTER only of the diagram that represents:

(a) An acoelomate

(b) A coelomate (2)

2.2.State TWO phyla that are represented by body plan B. (2)

2.3.From which embryonic layer does the tissue-filled layer develop? (1)

2.4.State the type of symmetry characteristic of organism B. (1)

2.5.Give TWO advantages of an exoskeleton in arthropods. (2)

(8)

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Activity 3
Diagram A shows a complete animal while diagram B shows cross section through the
body of the same animal.

3.1 Identify the phylum to which this organism belongs. (1)

3.2 What type of gut does this organism have? (1)

3.3 Explain ONE disadvantage of the type of gut named in Question 3.2. (2)
3.4 Explain ONE importance of the development of a coelom. (2)
(6)

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Activity 4

Study the diagram, which represent the body plans of two animals and answer the
questions that follow.

4.1. Provide labels for X and Y. (2)

4.2. Which body plan (A or B) represents an organism with radial symmetry? (1)

4.3. State whether body plan B represents a diploblastic or triploblastic animal. (1)

4.4.Give a reason for your answer to QUESTION 4.3. (1)

4.5.State TWO phyla that are represented by body plan B. (2)

4.6.Explain ONE advantage of the development of part Y to organisms with

body plan B (2)

(9)

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Activity 5

The diagram below shows the gut in an animal from one of the phyla you have studied.

5.1. State whether the animal has a blind gut or a through gut. (1)

5.2. Explain ONE advantage of the gut mentioned in 5.1. (2)

5.3. Name TWO phyla that have animals with a gut like the one in the
diagram. (2)

5.4. State what is meant by cephalisation. (2)

(7)

ACTIVITY 6

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The diagram below represents an organism in one of the phyla of the kingdom Animalia.

Locust

6.1 Identify the phylum to which the locust belongs. (1)

6.2 State whether the locust is diploblastic or triploblastic animal. (1)

6.3 Name the type of skeleton found in a locust. (1)

6.4 State TWO disadvantages of the type of skeleton mentioned in 6.3 and
explain how the locust overcomes each of these disadvantages. (4)

6.5 Explain why a blood system is necessary in coelomate organisms such as the locust (2)
(9)

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4.1. From the above phylogenetic tree, which group represents the ancestor of the
animal kingdom? (1)
4.2. How many animal phyla are shown on this tree? (1)

4.3. The first major split in the animal kingdom was into radial and bilateral
``````symmetry.
(a) Which phylum did not form a part of this split? (1)
(b) Which phylum has radial symmetry? (1)

4.4 The second split in the animal kingdom was based on the presence and
absence of a true coelom.
(a) Name the phylum that does not have a true coelom. (1)
(b) State ONE way in which the coelom of annelids and arthropods are different

from each other. (2)

4.5 From the diagram, identify ONE phylum you have studied which:

(a) Is diploblastic (1)

(b) Has a coelom and is bilateral symmetrical (1)
(9)

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Topic: photosynthesis

B. TERMINOLOGY

. Complete the following table by filling in the correct biological terms.

NO. Description Term

1. A process whereby green plants manufacture their own food

using radiant energy
2. Organelle in a plant cell where photosynthesis occur

3. Green pigment that trap light for photosynthesis

4. Occurs in the grana of the chloroplast

5. Occurs in the stroma of the chloroplast

6. Energy carrier in the living things used for various activities

7. Used to test for the presence of starch

8. Organisms that use light energy to manufacture its own food

9. A scientific procedure undertaken to make a discovery, test a

hypothesis or demonstrate a known fact.
10. Sugar that is the product of photosynthesis

11. Leaf that has more than one colour

12. Special building that is used for growing plants in an area where
they would not normally grow that well.
13. Process of eliminating starch reserves in a plant for experiments
concerning photosynthesis
14. A variable that is not changed throughout an experiment

15. Organisms that are unable to manufacture their own food

(consumers &decomposers)

16. A carbohydrate that store energy in plants

17. Factor that limits the rate at which photosynthesis takes place

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A. CLASSWORK/HOMEWORK

Activity 1

1.1 Various options are provided as possible answers to the following questions. Choose the
answer and write only the letter A to D) next to the question number in the answer book.

1.1.1

1.1.2

2x2=4 marks

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1.2 The diagram below represents the structure of a chloroplast.

1.2.1

1.2.2

1.2.3

Activity 2

2.1 Give the correct biological term for each of the following descriptions. Write only the term
next to the question numbers in the answer book.

2.1.1 (1)

2.1.2 (1)

2.1.3

2.1.4
2.1.5
2.1.6

2.1.7

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2.2 Indicate whether each of the descriptions in COLUMN I apply to A ONLY, B ONLY, BOTH
A AND B or NONE of the items in COLUMN II. Write A only, B only, both A and B or none next
to the question numbers (1.3.1 to 1.3.3) in the answer book.

2.2.1 The type of energy stored in food A: Chemical energy B:

molecules during photosynthesis Potential energy

Raw material(s) essential for A: Oxygen

2.2.2 photosynthesis B: Carbon dioxide

(4)

2.3 The following diagrams represent investigations involved in a process which takes
place in green plants. The plant/leaves represented as A and C were exposed to sunlight
for 4-5 hours.

2.3.1

2.3.2

2.3.3

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Activity 3

3.1 Study the equation below showing the formation of the energy carrier molecule X

ADP + P MOLECULE X

3.1.1 Give the full name of ADP (1)

3.1.2 Name molecule X (1)
3.1.3 Give one reason why molecule is biologically important.
(1)
Activity 4

4.1 The diagram below shows the set-up of an experiment to investigate whether carbon
dioxide is necessary for photosynthesis to take place. The plant was

destarched before the apparatus was set up as in the diagram and placed in a sunny room.

4.1.1 Name liquid C. (1)

4.1.2 Give the function of liquid C. (1)

4.1.3 What result can be seen at A? (1)
4.1.4 Explain ONE reason for the result at B. (2)
4.1.5 In which phase of photosynthesis will carbon dioxide be used? (1)
4.1.6 Where in the cell will the phase named in Question 4.1.5 take place? (1)
4.1.7 Why was the plant destarched before the experiment was conducted? (1)

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4.2 The graph below shows the rate of photosynthesis under different environmental
conditions. Study the graphs and answer the questions that follow.

4.2.1

4.2.2

4.2.3

4.2.4

4.2.5 4.2

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Activity 5

5.1 Study the diagram and then answer the questions.

5.1.1

5.1.2

5.1.3

5.1.4

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5.2 When light shines on pondweed, Elodea sp, bubbles of gas are released. The
rate at which bubbles of gas are produced can be used to measure the rate of
photosynthesis. An investigation was carried out to study the effect of different
colours of light on the rate of photosynthesis in the pondweed

The apparatus was set up as shown in the diagram below.

• The pondweed was exposed to one colour of light and left

for 5 minutes before measurements were taken.
• The time taken for the release of 20 bubbles was
recorded.
• The procedure was repeated using light of different
colours but of equal intensity.
• The results are given in the table below.

Colour of light Time (in seconds)for 20 bubbles to form

Violet 80
Green 40
Blue 160
Red 140
Yellow 70

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5.2.1

5.2.2

5.2.3

5.2.4

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5.3 An experiment was conducted to investigate the effect of light intensity and
the rate of photosynthesis. The apparatus was set up as shown in the diagram
below. Study the diagram and answer the questions

5.3.1

5.3.2

5.2.3

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Activity 6

6 6.1 Complete the missing words in the statements below:

6.1.1 As the light intensity increases, the rate of

photosynthesis______________ (1)

6.1.2 Structures in which crops are grown in a protected and controlled

environment are called _________________ (1)
ATP stands for __________________________
6.1.3 (1)

__________________ energy is found between phosphates.

6.1.4 (1)

6.1.2 Photosynthesis helps maintain a healthy level of carbon dioxide in the

__________________ (1)

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Activity 7

7.1 The diagram below shows a photosynthesis experiment done to investigate if a gas
is produced during the process. A small amount of sodium carbonate was added to
the water before the experiment was started.

7.1.1

7.1.2

7.1.3

7.1.4

7.1.5

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7.2 An experiment was set up to investigate whether oxygen is released during

photosynthesis. The result of the experiment is represented in the following
diagram.

7.2.1

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Activity 8

8.1 The graphs below (A, B, C and D) represent the relationship between the
rate of photosynthesis and temperature.

8.1.1

(2)

8.2 An experiment was carried out to calculate the rate of photosynthesis in a

group of plants at different concentrations of carbon dioxide. This was
repeated at two different light intensities. The results are given below.

8.2.1

8.2.2

8.2.3

8.2.4

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8.3 The diagram below shows how the leaf in a destarched plant was set up by
a learner to perform an experiment on photosynthesis. Study the diagram
and answer the questions below.

8.3.1

8.3.2

8.3.3

8.3.4

8.3.5

8.3.6

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Activity 9

9.1 Which ONE of the following factors will cause optimal growth in
greenhouses?

(2)

Topic: Animal nutrition

Complete the following table:

PART NUMBER FUNCTION
1
2
3
4
5
6
7
8

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10

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D. CLASSWORK/HOMEWORK

Activity 1

1.1 Provide the correct biological term for each of the following terms
1.1.1 Ejection of solid waste from the body
1.1.2 The breakdown of large insoluble food molecules into smaller water
soluble molecules so that they can be absorbed into blood plasma
1.1.3 The products of digestion become part of the protoplasm of the body
cells
1.1.4 4 The process of taking soluble food substances into blood stream

1X1=(4)

Activity 2

2.1 Study the following diagram about a part of human alimentary canal.

2.1.1 Give labels for the following parts:

(a) A (1)

(b) B (1)

(c) C (1)

(d) E (1)

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21.2 Give the LETTER of the part with the following function or
characteristics
(a) Responsible for the absorption of most water (1)

(b) Responsible for breaking down of food molecules by (1)

mechanical and chemical digestion
(c) Contains the sphincter muscle responsible for controlling (1)
defecation

2.1.3 State TWO functions of the liver associated with nutrition (2)
(9)

Activity 3

3.1 The diagram below shows a diagrammatic representation of the

digestive system

Mouth

Stomach

Small
P Q
intestine

Large
intestine

3.1.1 Name the part of the alimentary canal represented by X. (1)

3.1.2 By which process is food moved through structure X? (1)

Name the glands P and Q that release their secretions into the
3.1.3 (2)
small intestine.
3.1.4 Name the part of the alimentary canal where the digestion of
proteins begins. (1)
(5)

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Activity 4

4.1 Study the following diagram and then answer the questions by filling in the missing
words. Write the numbers 4.1.1 to 4.1.10 in your answer book and next to each the
missing word.

The diagram shows the structure of a ___4.1.1___ which is found lining the
___4.1.2___. The layer C consists of ___4.1.3___ cells. The part labeled D is
___4.1.4___ tissue. Parts A and B represent ___4.1.5___ into which the products
of digestion, ___4.1.6___ and ___4.1.7___, pass so that they can be transported
away. Vessel E represents the ___ 4.1.8 ___into which diffuses products of
digestion such as ___4.1.9___ and ___4.1.10___. (10)

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Activity 5

5.1 The diagram below shows a structure associated with the digestive system.

A
B

5.1.1 Identify the structure shown in the diagram. (1)

5.1.2 Name the following parts:

(a) A (1)
(b) B (1)
5.1.3 In which part of the digestive tract would this structure be found? (1)

5.1.4 Explain TWO structural adaptations of the part mentioned in (4)

QUESTION 5.1.3 that enables it to perform its functions
5.1.5 In which part (C or D) would you expect to find more nutrients? (1)

5.1.6 Explain your answer in QUESTION 5.1.5 (4) (13)

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Activity 6

6.1 A scientist conducted an investigation on digestion, involving gastric juice. She

compared the time taken for 50 g of different cooked egg samples to form chyme in
the stomach, with the time taken for the same sample to form chyme in a test tube
containing gastric juice. The test tube was maintained at 37 oC. The results are
indicated in the graph below.

6.1.1 Why was the temperature of the test tube maintained at 37 oC? (1)

6.1.2 Name ONE factor other than temperature which was kept constant during
the investigation (1)

6.1.3 Determine the following from the graph:

(a) The sample which took the longest time to form chyme in the
stomach (2)
(b) The sample which took the shortest time to form chyme in the test
tube. (2)

6.1.4 Describe the absorption and transportation of end product of food that
contains only carbohydrates. (8) (14)
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Activity 7

7.1 Study the flow diagram below.

7.1.1 Identify: - (a) Organ 1 (1)

(b) Hormone 2 (1)
(c) Hormone 3 (1)
7.1.2 The disorder caused when organ 1 fails to release amounts of hormone 2 (1)
7.1.3 The mechanism that controls the levels of glucose in the body (1)
(5)

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Activity 8

8.1 Read the extract below and answer the questions that follow.

TOO MUCH CARBOHYDRATES AND TOO LITTLE PROTEINS The World

Health Organisation (WHO) defines malnutrition as “the cellular imbalance
between the supply of nutrients and energy and the body’s demand for them to
ensure growth, maintenance, and specific functions.” The term protein-energy
malnutrition (PEM) applies to a group of related disorders. This involves
inadequate intake of protein and calories and is characterised by emaciation
(extreme thinness). The term was first used in 1933, and it refers to an inadequate
protein intake with reasonable caloric (energy) intake.
[Adapted from http://emedicine.medscape.com]

8.1.1 State the World Health Organisation’s definition of malnutrition. (2)

8.1.2 What condition can children suffer from if they get enough energy foods like bread,
rice and porridge but not enough proteins? (1)
8.1.3 Describe the chemical digestion of proteins in the stomach. (5)

(8)

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Activity 9
9.1 In general, people’s eating patterns can be divided into three basic kinds of diet based on
the type of protein eaten.
(a) Non-vegetarian diet: where people eat / drink all types of food

(b) Lacto-ovo diet: where people do not eat meat but do eat eggs milk, and milk
products
(c) Pure vegetarian diet: where people do not eat/ drink any animal-based food

The bar graphs below show the amount of energy contained in each of these three types of diets
per unit volume as well as the amount of energy needed to produce each type of diet.

9.1.1 Which of the above three diets requires the greatest volume of food to
be eaten? Give a reason for the answer. (3)
9.1.2 Suggest a reason why this diet named in QUESTION 2.2.1 might cause

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problems for very young children. (2)
9.1.3 What is the main source of proteins for pure vegetarians? (1)

9.1.4 Calculate the food energy intake that is provided by animals in the non- vegetarian diet,
as a percentage. (3) (9)

TOPIC: Cellular Respiration

D: ACTIVITIES (CLASSWORK/HOMEWORK)

Activity 1

Define the following terms:

a. Cellular respiration
b. Aerobic respiration
c. Anaerobic
d. Co-enzymes
e. ATP
f. Oxygen
g. Glycolysis
h. Mitochondrion
i. Kreb’s Cycle
j. Ethanol
k. Lactic acid
l. Carbon dioxide(CO2) (12)

Activity 2

2. Answer the following questions on cellular respiration.

2.1 Describe the process of cellular respiration (7)

2.2 Where in the cell does cellular respiration take place? (2)

2.3 Name the types of cellular respiration and describe the conditions required
for each to occur. (4)
2.4 List all the:
(a) requirements of cellular respiration (3)
(b) the product of cellular respiration (3)
2.5 Give the equation of aerobic cellular respiration (6)

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2.6 Discuss the reasons why cellular respiration is important for life on earth (8)

(33)

Activity 3

3. Answer the following questions on aerobic respiration.

3.1 Define aerobic respiration. (2)

3.2 List all the raw materials needed / required for cellular respiration. (3)

3.3 Draw a labelled structure of an organelle responsible for cellular (6)

respiration.
3.4 Discuss FOUR structural adaptations of mitochondrion to facilitate the
process of cellular respiration. (8)
3.5 Describe the process of aerobic respiration. (10)

3.6 Name the products of aerobic respiration. (3)

(32)

ACTIVITY 4

4.1 Study the investigation showing that oxygen is used by living organisms during cellular
respiration and answer the questions.

4.1.1 What is the role of the control in this investigation? (2)

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4.1.2 In which set up (experiment or control) would oxygen be still present after 12 - 24
hours? (1)
4.1.3 Give the reason to support the answer in question number 2.
(2)

(5)

4.2 Study the experimental design and answer the questions that follow.

4.2.1 State the aim of the experiment. (2)

4.2.2 Name the parts labelled A and B. (2)
4.2.3 State TWO precautions you would take in setting up this experiment.
Give a reason in each case. (4)

4.2.4 Explain the purpose of lime water? (3)

4.2.5 Explain how you would set up a control for this experiment. (2)

(13)

ACTVITY 5

5. Answer the following questions on anaerobic respiration.

5.1 Define what anaerobic respiration means. (2)

5.2 Describe how anaerobic cellular respiration occurs. (5)

5.3 State the significance of anaerobic respiration in industries. (3)

5.4 Tabulate differences between aerobic and anaerobic cellular

respiration, using the following criteria:
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• relative to amount of energy

• raw materials and products
(5)

(15)

Topic: Gas exchange

A. CLASSWORK/HOMEWORK

Activity 1

1.1

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1.1.1
(2)
1.1.2
(2)

1.1.3
(2)

(2)
[8]

Activity 2

1.1 Study the diagrams below showing some parts of the human respiratory system.
Answer the questions that follow.

1.1.1 (3)

1.1.2

(1)
1.1.3
1.1.2 (2)

1.1.4
(4)

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1.1.5
(5)
1.1.6

(4)
1.1.7
(2)
[21]

Activity 3

1.1 The following diagrams are based on the breathing mechanism and
gaseous exchange in the human body. The arrows represent the
movement of air/gases.

A B

1.1.1 Identify the phase in the breathing mechanism represented by A. (1)

1.1.2 Describe the changes that occur in the body to bring about the process
represented by B. (5)
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1.1.3 State TWO ways in which CO₂ is transported after it moves in the direction
indicated Y. (2)
[8]

Activity 4

1.1 Study the diagram showing parts of the human exchange system and answer
questions that follow.

1.1.1 Identify part A. (1)

1.1.2 Identify the process represented by 1 and 2. (1)
1.1.3 With regard to carbon dioxide and oxygen concentrations, which one will be
the highest at:
(a) X (1)
(b) Y (1)

1.1.4 List TWO features visible on the diagram which make the above
structure an efficient respiratory surface. (2)

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[6]

Activity 5
1.1

1.1.1
(1)

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1.1.2

(2)
1.1.3 (1)
1.1.4

(1)
(1)

1.1.5 (1)
1.1.6
(1)
1.1.7
(3)

[11]

Activity 6

1.1

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1.1.1
(2)
1.1.2

(3)

(2)
1.1.3

(2)
1.1.4

(5)
[14]

1.1

1.1.1
(1)
1.1.2
(1)

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1.1.3
(3)
1.1.4

(1)
[6]
Activity 7

Activity 8

1.1 An investigation was conducted to determine the effect of smoking on the

prevalence of other diseases. Study the table below and answer the
questions that follow.

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1.1.1 State the dependent variable for this investigation. (1)

1.1.2 Draw a bar graph representing the above information for active smokers (6)

1.1.3 State how many smokers per 100 000 die of heart disease. (1)

1.14 Indicate the ratio between active smokers, passive smokers and non- (2)
smokers that die of respiratory disorders.

1.1.5 Suggest TWO controlled variables that can improve this investigation (2)

1.1.6 What is the effect of smoking on the prevalence of lung cancer? Use the (1)
information in the table to explain your answer
1.1.7 Discuss the effect that smoking has on the bronchioles and alveoli of the (3)
lungs.

TOPIC : EXCRETION IN HUMAN

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B. CLASSWORK/HOMEWORK
Activity 1
Redraw the following table in your notebook and fill in the missing spaces.

ORGAN WASTE ORIGIN PRODUCT

PRODUCT/S EXCRETED
1. ____________ CO2 and water ________________ CO2 and water in
exhaled air
2. Skin (sweat ________________ Extracted from blood _________________
glands)
3. ____________ Urea ________________ ________________

________________ Breakdown of faeces

Haemoglobin
4. Colon ________________ Breakdown of ________________
Haemoglobin
Excess mineral ________________ faeces
salts
5. ____________ Urea ________________ Urine

________________ Excess taken in with Urine

food
Water ________________ Urine

Activity 2
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2. The diagram shows the structure of the human urinary system.

21 Provide labels for the parts A, B, G and I (4)

2.2 Identify the regions of the kidney marked C and D (2)
2.3 State ONE function of each of the following:
(a) E
(b) F
(c) H (3)
2.4 State THREE ways in which carbon dioxide is transported by the
blood vessel B. (3)
2.5 Write the NAME and the LETTER of the:
(a) Vessel that contains a relatively high
concentration of nitrogenous wastes. (4)
(b) Part where glomerular filtration occurs. (4)

Describe the functions of the kidney

2.6
(20)

Activity 3

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3. Study the diagram below of a longitudinal section through a kidney
and answer the questions that follow.

D
C

Longitudinal section of a human kidney H

3.1 Identify parts A, E and F. (3)

3.2 State the LETTER and NAME of the blood vessel that contains the
highest percentage of waste products. (2)
3.3 Why is region B darker in colour compared to region C in an actual
specimen? (2)
3.4 State the role of the fatty tissue surrounding the kidney. (2)
3.5 In which labelled oarts do each of the following occur?
(a) Malphigian bodies
(b) Loops of Henle (3)
3.6 (c) Ducts of Bellini (5)
3.7 Explain why urine in part G is sometimes very concentrated.
Explain how the functioning of the kidney will be affected if part G is (3)
blocked by a large kidney stone.
(20)

Activity 4

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Compile a table with the numbers A - M. In the next column complete the
labels for the numbered parts and in the last column indicate the function of
the part.

C
A

B
L
F G

H
M

D K

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Activity 5

5.1 Study the following diagram and table and answer the questions that
follow.

5.1.1 Label parts A, B and C (3)

5.1.2 Identify the processes indicated by 1, 2 and 3. (3)
5.1.3 Explain why there are a larger number of mitochondria in the cells of
the tubule in region 2. (2)
5.1.4 Explain the significance of the difference in diameter between
vessels A and D. (2)
5.1.5 Explain the role of part C in ensuring that concentrated urine is
excreted when there is a shortage of water in the body. (6)
(16)

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5.2 The diagram below represents the structure of the nephron.

The table below shows the concentration of some of the substances

found in the nephron of a human being.

Part of the Urea Glucose Proteins Salts

nephron g/100 cm3 g/100 cm3 g/100 cm3 g/100 cm3
2 0,03 0,10 8,00 0,72
3 0,03 0,10 0,00 0,72
6 2,00 0,00 0,00 1,50
5.2.1 Name the specialized cells found at part 1. (1)
5.2.2 Which substance:
(a) Did not pass from part 2 to part 3
(b) Was completely reabsorbed from part 3 (1)
5.2.3 Calculate the difference in the salt concentration between part 3 and (1)
part 6. Show all working.
5.2.4 Explain why the concentration of urea is greater in part 6 than in part
3. (3)
(2)
(8)

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Activity 6
6.1 Study the table below which shows the flow rate and concentration of certain
substances taken at regions A, B, C and D of the nephron in the human
kidney.

Part of Flow rate Solute concentrations

the (cm3/min) (g/100 cm3)
nephron
Proteins Glucose Sodium Ammonium Urea
ions ions
A 4 0,0 0,0 0,6 0,04 1,80
B 200 0,0 0,10 0,72 0,0 0,05
C 40 0,0 0,0 0,3 0,0 0,15
D 2 000 7,0 0,10 0,72 0,0 0,05

6.1.1 State, with a reason, which of the parts (A, B, C or D) of the

nephron represent the following:
(a) Afferent arteriole (2)
(b) Bowman’s capsule cavity (2)
(c) Loop of Henlé (2)
(d) Duct of Bellini (2)
6.1.2 Explain the difference in the flow rate between B and D. (5)
6.1.3 What conclusion could you make if the value for protein in A was
0,5 g/100 cm3? (2)
6.1.4 State TWO functions of the kidneys, other than pH regulation, that
can be supported by the data given in the table. (2)
6.1.5 Will there be amino acids in A in a healthy person?
State ONE reason for your answer. (2)
6.1.6 (a) Name the inorganic substance, shown in the table, that can
pass out against a concentration gradient from the renal
tubule into the medulla of the kidney. (1)
(b) Why is it necessary for this substance to move out of the (2)
renal tubule?

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6.1.7 Explain TWO ways in which the Bowman’s capsule is structurally (4)
suited for its function.
6.1.8 Account for the increase in Sodium ions between parts C and A. (4)
(30)

6.2 Study the table below and answer the questions that follow.

6.2.1 Which substance(s)present in the plasma did not filter into the
Bowman’s capsule? Give a reason for your answer. (2)
6.2.2 Provide an explanation for each of the following:
(a) No glucose in the urine
(b) A higher concentration of salts in the urine compared to the
6.2.3 filtrate (3)
State ONE possible reason why glucose is sometimes present in the (3)
6.2.4 urine of a person.
(2)
Could the composition of the urine shown in the table be that of a
dehydrated person? Explain your answer.

(3)
(13)

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Activity 7
7. The following graph indicates the concentrations of certain
substances as they move through the various regions of the nephron.
Study the graph and answer the questions that follow.

7.1 Name the regions indicated by A and B. (2)

7.2 Which of the substances indicated on the graph is not excreted as
part of urine? (1)
7.3 Which product, according to the graph, occurs in a higher
concentration in urine than in the blood entering the kidney? (1)
7.4 Explain the changes in the glucose concentration during the
movement through region B. (5)
7.5 Explain the decrease in water concentration in the distal convoluted
tubules. (6)
(15)

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Activity 8

8.1 The diagram below shows a part of a kidney machine which is used
in cases of kidney failure. Study the diagram and answer the
questions that follow

blood back to the

blood patient
from the
patient

folded tubes

dialysis fluid

Part of kidney machine

8.1.1 Explain why the tubes are folded rather than straight. (2)
8.1.2 Explain ONE requirement that the material which makes up the folded
tubes, should meet to ensure effective functioning. (2)
(4)
8.1.3 Describe the composition of the dialysis fluid for the effective
functioning of the kidney machine. (2)
8.1.4

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Give TWO reasons why a successful kidney transplant would be
better for
a patient than treatment on a kidney machine.
(10)

8.2 The figure below shows how a kidney dialysis machine works. The
machine works on similar principles as a real kidney.

8.2.1 Why must the membrane separating the blood from the dialysis fluid
be selectively permeable? (2)
8.2.2 What must the composition of the dialysis fluid be?
Give a reason for your answer. (4)
8.2.3 At what temperature must the dialysis fluid be kept? Why? (2)
8.2.4 Why might it be dangerous if air bubbles got into the patient’s blood? (2)
8.2.5 Give two reasons why a successful kidney transplant would be better
than treatment on a kidney machine. (2)
8.2.6 Which vessel (R or S) is an artery? Give a reason for your answer. (3)

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8.2.7 Tabulate TWO differences in the composition of blood at point A and
at point B. (5)
8.2.8 State TWO similarities in the composition of blood at point A and at
point B. (2)
(22)

Activity 9

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Complete the missing information in the table below.

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Activity 10

10.1 Discuss THREE ways how each of the following parts of the
kidney are structurally suited to perform its function:
10.1.1 Malphigian Body (6)
10.1.2 Renal tubule
(6)

(12)

10.2 Answer the following questions on the regulation of water in

mammals.
10.2.1 Will a mammal that spends most of its life in fresh water have a
well developed loop of Henlé? Explain your answer. (3)

10.2.2 Will a high ADH concentration increase or decrease blood

pressure? Explain your answer. (3)
(6)

10.3 Describe the role of the kidney in the regulation of blood pH. (6)

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Topic: Population Ecology

C. CLASSWORK/HOMEWORK

Activity 1

1.1 Provide the correct term for each of the following

descriptions
1.1.1 A pattern of relationships among individuals that benefits the 1
society
1.1.2 Method of determination of population size by counting the 1
individuals in a representative sample area
1.1.3 Competition for resources between individuals of the same 1
species
1.1.4 Co-existence of different species living in the same habitat by 1
using
resources differently
1.1.5 A symbiotic relationship in which one organism benefits and the 1
other one is unaffected
1.1.6 The death of individuals in a population 1
1.1.7 Countries with a characteristic high birth rate and decreased life 1
expectancy
1.1.8 A group of organisms of the same species, occupying a particular 1
habitat and having the ability to interbreed randomly
1.1.9 The inherent ability of a population to increase by birth 1
1.1.10 The tendency of certain species to defend an area within a habitat 1
that they occupy against intruders
1.1.11 The killing of elephants through hunting in order to regulate their 1
population size

Activity 2

2.1 Various options are provided as possible answers to the following

questions. Write down the question number (1.1.1 to 1.1.10), choose
the answer and make a cross (X) over the letter (A to D) of your choice
in the ANSWER BOOK.
2.1.1 Which one of the following contains two factors that contributes to an
INCREASE in population size?

A natality and emigration

B lmmigration and natality

C emigration and immigration

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D mortality and natality 2
2.1.2 The mark-recapture-mark method of a population size estimation can
be

A animals become trap-shy and cannot be caught.

B animals are left for a year before recapture.

C no immigration occurs.

D markings are temporary 2

2.1.3 An individual becomes infected with bilharzia parasite (Schistosoma)

when

A urinating in freshwater

B an individual infected with bilharzia parasite urinates in water

C an individual comes into contact with fresh water contaminated

with bilharzia parasite

D when swimming in fresh water together with a friend infected with

bilharzia parasite 2 6

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Activity 3

3.1 Graph A below represents the number of bacteria in a growth culture

over a period of time. Graph B shows changes in the human
population size over a period of time.

3.1.1 Explain the pattern of growth during period A in Graph A 2

3.1.2 Explain the pattern of growth during the first few hours of the 2
investigation, before period A in Graph A.

3.1.3 In what way is the growth of human population (Graph B) similar to 1

that of bacterial population (Graph A)?

3.1.4 Explain why it might take the human population longer to reach the 2
type of growth shown by bacteria population in period B.

3.1.5 State TWO precautionary measures that may be implemented in 2

South Africa to slow down the growth in the population.
9

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Activity 4

4.1 The data table below shows the estimated human population
measured at different times.
YEAR ESTIMATED POPULATION
(MILLIONS)
1650 500
1850 1000
1900 1500
1925 2000
1950 2500
1960 3000
1975 4000
1999 6000
2011 7000
4.1.1 Draw a line graph to represent the data in the table. 6

4.1.2 What is the shape of the curve you have drawn? 1

4.1.3 How long did it take the population of the world to increase from 500 1
million to 1000 million (I billion)?

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Activity 5

5.1 The diagram below represents ecological succession in a forest over

500 years.

5.1.1 What is ecological succession? 2

5.1.2. Name the type of ecological succession shown in the diagram. 1
5.1.3. Explain your answer in the above Question
2
5.1.4. Identify two examples from the diagram that can be regarded as part
of pioneer community in this habitat. 2

5.1.5 Explain the importance of the pioneer species in the type of the
ecological succession you identified in QUESTION 3.1.4 above. 2

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Activity 6

6.1 The Colorado Beetle is a pest because it feeds on potato crops. In

an investigation, the population of beetles in 2000 m2 potato field
estimated as described below: -

• A sample of beetles was collected from the field and counted

• Each beetle was marked with a spot of paint then released
back into the field
• Three days a second sample was collected and counted
• The number of marked beetles in this second sample was
noted
The results are shown in the table below

Number of beetles Number of beetles in Number of marked

that were marked the second sample beetles in the
and released second sample
500 450 5

The population of beetles can be estimated using the following

formula:

P=MxC
R

P = population estimate
M = number of beetles captured and marked
C = number of beetles captured
R = number of marked beetles in the second capture

6.1.1 Calculate the population size of the beetles in the field. Show all
calculations 3
6.1.2 State whether the population size of the beetles will be
UNDERESTIMATED or OVERESTIMATED under the following
conditions
(a) Some of the on the beetles were off before the second catch 1

(b) The second sample is taken from the same place as the first,
long after the first sample was taken 1
5
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Activity 7

7.1 Read the extract on South Africa’s human population growth and
answer the questions that follow.
In 2010, South Africa’s population was 49,1 million. By 2011, the
population had increased to 50,5 million. Around 33 % of the current
population is younger than 15 years and 40% of the population is
between 15-35 years. Statistics predicts that the proportion of young
people (15-35 years) will increase in the future. There is growing
demand by the young for free tertiary education. Due to a decrease in
income tax revenue and increased unemployment this demand will be
difficult to meet. Every South African needs to contribute towards the
economy and concentrate on ways of using our resources in a more
sustainable manner.
7.1.1 What percentage of the current population is 35 years and younger? 1
7.1.2 State TWO reasons why for planning purposes it is important for the
government to look at projected growth in the population. 2
7.1.3 State TWO reasons, according to the extract, why providing free
tertiary education is problematic for the government. 2
7.1.4 Explain ONE possible consequence for the economy if we do not 2
use ‘our resources in a more sustainable manner’.
7

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Activity 8

8.1 Study the information given in the table draw the table in your answer
book and provide answers in spaces provided

Type of interaction reason

Hummingbird

Flea bites on human

Egret waiting for rhino

to disturb insects to eat
8.1.1 Identify the type of the interdependence in each case and give one 6
reason for your answer
6

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TOPIC : HUMAN IMPACT ON ENVIRONMENT

4. TERMINOLOGY
Give the correct biological term for the following descriptions.
NO. Description Biological term
1. A process by which nutrients become highly concentrated in a body of
water, leading to increased growth of organisms such as algae.
2. Measurement of the total amount of carbon dioxide emissions of an
individual, a defined population or a company per year.
3. The type of pollution caused when water is released into a river after
being heated in power stations or industries.
4. A layer in the atmosphere that is damaged by chlorofluorocarbons
(CFCs).
5. Measurement of the total amount of carbon dioxide emissions of an
individual per year.
6. Having access to enough food on a daily basis to ensure healthy living.

7. The illegal removal of organisms from their habitat

8. The variety of plant and animal species on Earth

5. ACTIVITIES
Activity 1: Read the passage below.

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Activity 2
2. Read the passage below which deals with methane emissions around the world.

2.1 According to the information in the passage, what can be regarded as a danger of
methane? (1)

2.2 Describe to what extent certain municipalities in South Africa could use the decay
of organic waste emitting methane to their advantage. (2)
Activity 3
The table below shows the estimated percentage of global methane emissions for
2010 from different sources.

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3.1 (a) Calculate the value of X. Show all calculations. (2)

(b) Draw a pie chart that will represent the information as illustrated in the table above. (6)

Activity 4
4.1 Read the article below

4.1.1 According to this passage, mention TWO ways in which food

security in Africa could improve. (2)

4.1.2 Besides poor farming practices, name ONE other factor, mentioned
in the article that may be the cause of decreased crop production in
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Africa. (1)

4.1.3 Give ONE reason, according to the article, why there is reduced
water availability to farms in Africa. (1)

4.1.4 Describe how the use of fertilisers may lead to reduced water quality. (4)
(8)

Activity 5
A group of learners wanted to investigate the effect of temperature on oxygen solubility. They
collected water samples along a river, situated next to many industries that use water from
the river for cooling purposes. Learners used the same type of thermometer to measure water
temperature.
5.1 Formulate a hypothesis for the investigation above. (2)

The results obtained, are indicated in the table below:

Temperature (°C) O2/100 g H2O
0 7,0
10 5,4
12 4,2
17 3,5
23 3,0
25 2,5
28 2,2
32 2,0
34 1,8
41 1,7
42 1,7
[Adapted from: Introduction to Chemistry]

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5.2 What effect would the releasing of water at higher temperatures have on organisms living
in the river? (2)

5.3 Why was it important for learners to use the same type of thermometer? (2)
5.4 State ONE way to improve the reliability of the results. (1)
(7)

Activity 6

A group of learners collected water samples at different places (X, Y and Z) along the same
river to compare the level of substances (oxygen and waste) as well as the organisms present.
The graph below shows the changes in the amount of substances (waste and oxygen) in the
water along the course of the river. The point at which sewage enters the river is indicated.

The presence or absence of certain animal species can be used as indicators of the degree of
water pollution in a river, as shown below:

Organism Present Degree of water pollution

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Mayfly nymph Unpolluted

Leeches Moderately polluted

Sludge worms Severely polluted

6.1 Which organism (listed in the table) would most likely have been present at:X Y (2)
6.2 State TWO factors that should be kept constant while collecting the
water samples. (2)
6.3 Name the dependant variable in this investigation. (1)
6.4 Explain how the entry of sewage will affect the amount oxygen in the water (5)
(10)

Activity 7
7.1 Describe the advantages and disadvantages of landfills as a (6) solution to land
pollution and disposal of solid waste.

Activity 8
8. Study the bar graph below and answer the questions that follow.

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8.1 By how much did the level of sulphur dioxide pollution in Sweden decrease between
2000 and 2005? (1)
8.2 Compare the general pattern of air pollution levels of France to that of the other countries.
State the following:
(a) ONE similarity (1)
(b) ONE difference (2)
8.3 Which country had the lowest level of sulphur dioxide pollution in 2005? (1)

Activity 9
9.1 Read the passage below and answer the questions.

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'
9.1 Define biodiversity (1)

9.2 Explain why the increased phosphate levels caused a decrease in biodiversity. (3)
9.3 Explain how the reduction in biodiversity can affect the ecological balance in
the dam. (4)
9.4 What is meant by biological control? (2)

Activity 10
10.1 Boll weevil insects, shown in the picture below, feed on cotton plants. There are two
varieties of the cotton plant, original variety (V) and boll weevil resistant variety (R).

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Three farms were used to compare the yield of the two varieties. Each farmer planted two fields,
one of each variety. All fields were treated identically.
The yield of cotton from each field was weighed. The results are shown in the bar graph below.

10.1 Calculate the difference in yield between the two varieties of cotton grown at Farm X.
Show all workings. (3)
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10.2 Name the variable that was changed in this investigation. (1)
10..3 The fields planted with V cotton were used as a control. Give a reason for
using V cotton as the control. (2)
10.4 Explain why using ten farms instead of three would have improved this
Investigation. (2)
10.5 State a hypothesis for this investigation. (3)
10.6 What conclusion can be drawn from these results? (3)
10.7 The farmers use pesticides to kill insects which damage their crops. Explain why less
pesticide is needed when growing R cotton than when growing V cotton. (2)
10.8 Would an increase in the prevalence of R cotton over V cotton be an example of artificial
selection , natural selection or both? Explain your answer. (4)

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Life Sciences JIT 3 of 2020

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