1

Key Area 1.1 - CELL STRUCTURE

Exercise 1

Research task on unicellular organisms

After doing some research, choose one example of a unicellular

organism (single celled organism).

Make a labelled drawing of the organism.

Write a paragraph describing where it lives and how it obtains its

food.

Write a list of references you used at the end.

Exercise 2

1. Name THREE structural features that a typical plant cell and a

typical animal cell have in common. (3)

2. Name THREE structural features present in an Elodea leaf cell but

absent from a cheek cell. (3)

3. Give the function of each of the following structures: cell

membrane, cell wall, nucleus. (3)

Total (9)

2

Exercise 3

1a) Identify FOUR structural features that a yeast cell has in common

with an Elodea leaf cell. (4)

b) Name ONE structure absent from a yeast cell but present in

Elodea. (1)

2 A yeast cell can divide to form 2 cells in 30 minutes.

10 yeast cells are placed in a sugar solution.

a) How many yeast cells will be present after 2 hours? (1)

b) How long will it take for there to be over 1000

yeast cells? (1)

c) Name the process by which yeast cells reproduce. (1)

3 Give the function of these cell structures.

a) Mitochondria

b) Ribosomes

c) Chromosomes (3)

4 Bacterial cells have a main coil of DNA and other smaller rings

of DNA.

a) What name is given to the smaller rings of DNA? (1)

b) What is their function in bacterial cells? (1)

c) What type of microscope is needed to see details of cell

structures in small cells? (1)

Total (14)

3

Exercise 4

Research task on yeast

Research the uses of yeast in industry.

Describe the ways in which yeast is used in two different industrial

processes. Write your information in two separate paragraphs.

Write a list of references you used at the end.

Exercise 5

Exam style questions

1. The diagram below represents a plant cell.

Which of the labelled parts of the cell are also found in an

animal cell?

A M and N

B N and O

C M and P

D M, N, O and P

2. The diagram below represents a unicellular organism.

Which part indicates this is a plant cell?

4

3. Which line in the table below correctly matches the plant cell

structure to its function?

4. Which structural feature is common to both plant and animal cells?

A Cell wall

B Chloroplast

C Nucleus

D Large central vacuole

5. Which of the following prevents bursting of plant cells?

A Nucleus

B Cytoplasm

C Cell wall

D Cell membrane

Plant cell structure

Function

A Cytoplasm Controls the chemical

activities

B Cell wall Keeps the cells turgid

C

Vacuole

Prevents the cell from

bursting in a hypotonic

solution

D

Cell membrane Controls which molecules

enter or leave the cell

5

6. Which plant cell structure is made of cellulose?

A Cell wall

B Cell membrane

C Chloroplast

D Nucleus

7. The diagram below shows onion cells as observed under a

microscope at a magnification of 100 X.

300 micrometres

The diameter of the field of view is 300 micrometres. The

average width of each cell in micrometres is

A 0.38

B 0.75

C 37.5

D 75.0

6

Question 8 and 9 refer to the diagrams of cells below.

8. Which cells are plant cells?

A P only

B P and Q

C P and R

D R only

9. The function of structure X is to

A control all cell activities

B keep the cell turgid

C produce glucose using light energy

D release energy from glucose

7

10. Which line in the table below describes correctly the functions of

the cell wall and chloroplasts in plant cells?

11. The diagram below shows a plant cell and an animal cell.

(a) Identify structure X.

(b) Give a function of the nucleus.

(2)

Function of cell wall

Function of chloroplast

A prevents cell

bursting respiration

B controls entry of

substances respiration

C prevents cell

bursting photosynthesis

D controls entry of

substances photosynthesis

8

12. The diagrams below show sections of three different cell types.

They are not drawn to the same scale.

(a) (i) Copy and complete the table below to show the name

and function of the parts labelled, X, Y and Z.

(ii) Cells A and B are plant cells and cell C is an animal cell.

Describe two features, shown in the diagrams, that support

this statement.

(5)

13. Copy and complete the table.

Cell Structure Function

Site of aerobic respiration

Ribosomes

Small rings of DNA in bacterial cells

for reproduction

(3)

Total (20)

Part of cell Name Function

X

Y

Z

9

Exercise 6

Research task on bacteria

Choose one of the following research tasks:

A Research the uses of bacteria in the dairy industries.

Describe how bacteria are used in the production of two

different foods. Write your information in two separate

paragraphs.

Write a list of references used at the end.

OR

B

Research diseases caused by bacteria

Describe two bacterial diseases, their symptoms and treatment.

Write your information in two separate paragraphs.

Write a list of references used at the end.

10

Key Area 1.2 – TRANSPORT ACROSS MEMBRANES

Exercise 7

1. Name the two types of molecule present in the cell membrane. (2)

2. The cell membrane is sometimes described as a fluid mosaic

structure.

a) Why is it described as fluid?

b) Why is it described as a mosaic? (2)

3. Cell membranes are selectively permeable.

a) What does this mean?

b) Name one substance which can pass through a cell membrane

easily.

c) Name one substance which cannot pass through cell

membranes.

d) Why is this substance unable to get through the membrane?

(4)

4. a) Name an artificial material used in experiments which is

selectively permeable.

b) Describe the test for starch.

c) What colour change would indicate a positive result for

glucose with Benedicts solution? (3)

Total (11)

11

Exercise 8

Make a 3D cell membrane model

Your task is to make a 3D model of the cell membrane.

You can use any materials you can find at home, especially recycling

materials.

Your model should show the proteins and the phospholipids with

their head and tail ends.

The component parts should be labelled or there should be a key a

identify them.

Examples of materials you could use include paper, cardboard,

plastic bottle lids, plasticene, playdoh, straws, cotton buds, cocktail

sticks, buttons, ribbons, fabric, lolly sticks, dry pasta, Lego, stickle

bricks, k’nex.

THE POSSIBILITIES ARE ENDLESS SO HAVE FUN

Exercise 9

1. Name the two types of passive transport. (2)

2 a) Name TWO essential substances that enter an animal cell

by diffusion. (2)

b) Name a waste material that diffuses out of an animal cell.

(1)

c) What structure controls the passage of substances into and

out of a cell? (1)

3 a) Explain why diffusion is important to human beings. (2)

b) Predict what would happen to the rate of diffusion of oxygen

into muscle cells if a person exercised vigorously. Explain

your answer. (2)

Total (10)

12

Exercise 10

Research task on diffusion in the lungs

Do some research on diffusion in the lungs.

Make sure you find out about both of the main gases involved.

Write a paragraph about this diffusion.

Draw a diagram to show what happens, or print and stick in a

diagram.

Make a list of the references you used at the end.

Exercise 11

1. Define the term diffusion. (1)

2. a) Describe the change in mass undergone by a cylinder of

fresh beetroot when it is immersed for 24 hours in

(i) water

(ii) concentrated sucrose solution (2)

b) What name is given to the special type of diffusion that

causes these changes? (1)

c) What substance is gained or lost by the beetroot cells

during this process? (1)

3. a) Define osmosis using these terms:

Lower water concentration, net movement, membrane, water molecules, higher water concentration. (3)

b) Using the terms selectively permeable membrane and

concentration gradient of water, explain how the process of

osmosis occurs. (2)

13

4. The diagram below shows four plant cells, P, Q, R and S.

If the plant cells remained in contact as shown, then water would

pass by osmosis from BOTH:

A R to Q and Q to P

B Q to S and R to Q

C P to Q and R to S

D Q to P and Q to R (Choose ONE answer only) (1)

5. Three identical cylinders of fresh turnip were immersed in the

liquids as shown below for 24 hours. Each was then removed and

held between forefinger and thumb as shown in the second

diagram.

a) Match numbers 1, 2, and 3 with letters A, B and C. (1)

b) Explain your choice in each case. (3)

Total (15)

14

Exercise 12

Research task on paramecium

Paramecium is a single celled animal that lives in fresh water.

Find out why it does not burst due to osmosis.

Make a labelled drawing of paramecium.

Describe how paramecium copes with the intake of water by

osmosis.

Make a list of the references you need at the end.

Exercise 13

1 a) Explain why red blood cells burst when placed in water yet

onion epidermal cells do not. (2)

b) Why do red blood cells shrink when placed in concentrated

salt solution? (1)

2 a) Describe the effect of very concentrated salt solution on

onion epidermal cells. (1)

b) Explain why this happens. (1)

c) What name is given to cells in this state? (1)

d) How could these cells be restored to their turgid condition?

(1)

3 Make a labelled drawing of a plasmolysed cell. (3)

Total (10)

15

Exercise 14

1 a) Define the terms active transport. (1)

b) State two ways in which active transport is different from

diffusion. (2)

c) Give an example of active transport in living cells. (1)

d) What molecules in the cell membrane are involved in active

transport? (1)

2 The diagram below shows the direction of movement of two

different substances through the cell membrane of an animal cell.

a) Name processes X and Y. (1)

b) Which of these processes requires energy? (1)

c) Which of these processes does not occur in dead cells?

(1)

Total (8)

cell membrane

16

Exercise 15

Exam style questions

1. The following diagram shows the fluid-mosaic model of the

structure of a cell membrane.

Which pair of structures numbered in the diagram are correctly

identified in the following table?

PROTEIN PHOSPHOLIPID

A 1 7

B 2 4

C 3 7

D 5 6

2. Diffusion is the movement of molecules of a substance from a

region of:

A high concentration to a region of low concentration of

the same substance

B low concentration to a region of high concentration of the

same substance.

C high concentration to a region of low concentration of a

different substance.

D low concentration to a region of high concentration of a

different substance.

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3. Diffusion is important to the unicellular animal Amoeba because it

is the means by which

A oxygen, a useful substance, enters and CO2, a waste product,

leaves.

B CO2, a useful substance, enters and oxygen, a waste product,

leaves.

C oxygen, a waste product, enters and CO2, a useful substance,

leaves.

D CO2, a waste product, enters and oxygen, a useful substance,

leaves.

4. The movement of water through a selectively permeable

membrane from an area of high water concentration to an area of

low water concentration is called

A absorption

B osmosis

C plasmolysis

D active transport

5. A piece of potato weighs 20 g fresh and 5 g dry.

What is the percentage water content of the potato?

A 5%

B 15%

C 25%

D 75%

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6. When animal cells are placed in water they

A remain unchanged

B burst

C plasmolysed

D become turgid

Question 7 and 8 refer to the accompanying diagram.

It shows the results of an experiment where turnip

cylinders, initially measuring 5 cm in length, were

immersed in three different liquids for 24 hours.

The test tubes were kept in a thermostatically

controlled water-bath during this time.

7. Which line in the following table correctly identifies liquids X, Y

and Z?

Bathing liquid

X Y Z

A 1 % sucrose 0.3 % sucrose Pure water

B 1 % sucrose Pure water 0.3 % sucrose

C 0.3 % sucrose 1 % sucrose Pure water

D 0.3 % sucrose Pure water 1 % sucrose

8. The factor that was varied in this experiment was

A temperature of bathing liquid

B length of turnip cylinder

C concentration of sucrose solution

D diameter of turnip cylinder

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9. The accompanying diagram shows four red onion cells immersed in

four different solutions P, Q, R and S.

If the bathing solutions were arranged in order of increasing water

concentration, the sequence would be:

A R, Q, S, P

B R, S, Q, P

C P, Q, S, R

D P, S, Q, R

10. Three plant cells, P, Q, R are shown below.

a) Water is moving from cell P to cell Q and from cell Q to cell R.

Which cell has the highest water concentration? (1)

b) If all three cells were placed in pure water for one hour, what term

would be used to describe the resulting appearance of the cells?

(1)

20

11. Three similar cylinders were cut from the same potato, dried and

weighed. Each cylinder was placed in a different solution as shown

in the diagram below.

0.5% Salt solution 1% salt solution water

After one hour, the cylinders were removed from the solutions, dried and

reweighed.

(i) Copy and complete the table below by using the information in the

diagrams.

(1)

(ii) Which process has caused these changes in weight? (1)

(iii) The diagram below shows a cell from one on the potato cylinders.

What term would be used to describe the condition of this cell?

(1)

Solution Initial weight (g) Final weight (g)

10 8

10 10

10 12

21

12. The diagram below shows the unicellular organism Paramecium

which lives in fresh water.

a) Name the process by which oxygen moves from the water

into the organism. (1)

b) Name a substance that moves from the organism into the

water. (1)

d) Name the cell structure which controls the entry and exit of

materials. (1)

Total (16)

22

Key Area 1.3 - MAKING NEW CELLS

Exercise 16

1. What name is given to the type of cell division that produces two

cells that are identical to the parent cell? (1)

2. State the main events that occur during this cell division in an

animal cell. (2)

3. Which cell structure controls cell activities including cell division?

(1)

4. Arrange the stages of mitosis (shown below) in the correct

sequence beginning with (b.) (5)

5. Describe the process of mitosis (nuclear division) in a cell including

the terms equator and spindle fibres in your answer.

(4)

6. Why is it important that the chromosome number of new daughter

cells in a multicellular organism is maintained? (1)

7. What process maintains this continuity? (1)

Total (15)

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Exercise 17

Part 1:

Using 1 piece of A4 paper produce a cartoon strip/storyboard to explain

the stages involved in the process of mitosis.

Use the following steps to help you:

The original cell contains single-stranded chromosomes.

When the cell is preparing to divide, each of the chromosomes is

copied to form a double-stranded X-shaped chromosome.

A spindle forms in the cell. The chromosomes line up along the

centre (equator) of the cell.

The spindles pull the chromosomes apart.

The single-stranded chromosomes reach opposite ends of the cell.

The cell splits into two, producing two genetically identical

daughter cells.

Extension Try to include the word diploid in your explanation.

Total (7)

Part 2:

Answer the following questions in full sentences:

1. What is mitosis? (1)

2. Why is mitosis important? (2)

3. What would happen if mitosis didn’t take place? (1)

4. What is meant by a diploid cell? (1)

5. What cells in the body do you think are not diploid? (1)

Total (6)

Exercise 2 total (13)

24

Exercise 18:

Culturing Bacterial Cells Instruction Manual

Your task is to create an instruction leaflet on how to safely culture

bacterial cells.

You must include:

What cell culturing is and why bacteria can be used.

You should include:

A step by step guide to explain how to safely culture (grow)

bacterial cells, you may include diagrams.

You could include:

A detailed description about the health and safety involved in

culturing bacterial cells (aseptic technique)

This work will be graded A, B or C.

Exercise 19:

Answer each of the Learning Outcomes for Unit 1 Topic 3: ‘Making New

Cells’ as full sentences.

You may present this information in any way you wish; you may produce a

mind-map, a poster, a pamphlet, use diagrams or pictures etc…

Total: 14 Marks

Exercise 20

Make a poster on ‘Aseptic Techniques’

You must include;

At least five different techniques – with diagrams - used to ensure

conditions are sterile in a lab.

Total (10)

25

Exercise 21

Answer the following questions in full sentences:

1. What does the word optimum mean? (1)

2. Name the two types of medium that are used to grow cells in

Biology? (1)

3. Name three conditions that are required for cells to grow (3)

4. Give the name of the large vessels in which bacteria or fungi are

grown. (1)

5. Give three conditions that are required for growth in these

vessels. (3)

Total (9)

Exercise 22

Exam Style questions

1. The diagrams below show six stages of a cell process.

The stages are shown in pairs. The diagrams in each pair are in the

correct order. The three pairs of diagrams are NOT in the correct

order.

(a) Name the process shown in the diagrams.

__________________________________________________ (1)

(b) Write the letters of each pair in the order in which they occur in this

process.

1. _____________ 2. ______________ 3. _____________ (1)

(c) Name the cell structure which controls this process

___________________________________ (1)

(a) (b) (c)

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2. A cell can divide to produce two daughter cells. Each daughter cell

grows and then divides.

The beginning of these divisions is shown in the diagram below.

Calculate the number of cells in the 4th generation.

Space for calculation

Answer: __________ cells (1)

3. The diagram below shows some of the stages in cell division occurring

in the cells of a plant root. Describe the stages of cells division

(mitosis) shown in the cells labelled X, Y, and Z.

1st division

2nd division 1st

generation 2nd

generation

27

X: _______________________________________ (1)

Y: _______________________________________ (1)

Z: _______________________________________ (1)

4. Describe the meaning of the term ‘diploid cell’

__________ (1)

5. Typical timings of the stages of mitosis are shown in the table below.

What percentage of the total time for mitosis is taken by stage C?

Space for calculation Answer: _____________% (1)

6. Name the structure within a cell which controls cell division.

(1)

7. Below is a diagram of a human cell. Name the structure labelled X.

(1)

Stage A B C D

Time (minutes) 88 33 25 54

X

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8. Complete the following sentences by deleting the incorrect word from

each pair to create a correct sentence. Write out in full.

The number of chromosomes in the new cells produced by cell

division will be the same as/half that of the parent cell.

During cell division each parent cell produces two/four new cells.

The cells produced by cell division will be different/identical to

each other. (3)

9. Cell division can be described as a controlled cycle. What might occur

if cell division is uncontrolled?

(1)

10. An onion cell contains 16 chromosomes. It divides to form two new

cells, which then divide again. How many chromosomes will these new cells

have? (1)

Total (16)

29

Key Area 1.4 – DNA AND THE PRODUCTION OF

PROTEINS

STRUCTURE OF DNA

Exercise 23

Research Task on DNA Structure

Research one of the following scientists and write a short report on how

their work has helped us to understand the structure of DNA. Provide a

list of references at the end.

Francis Crick

James Watson

Rosalind Franklin

Maurice Wilkins

Erwin Chargaff

Exercise 24

1. What are chromosomes and where are they located in a cell? (1)

2. a) What do the letters DNA stand for? (1)

b) The DNA molecule is described as a ‘double helix’. What does

this mean? (1)

c) i) How may different types of base molecule are found in DNA? (1)

ii) Name the four base molecules. (4)

iii) Describe the base pair rule. (1)

Total (9)

30

Exercise 25

The diagram below shows a yeast cell.

(i) Name the structure shown in the yeast cell which contains the

genetic information. (1)

(ii) A molecule consisting of chains of bases is contained in

chromosomes.

(a) Name this molecule. (1)

(b) Explain how this molecule controls cell activities. (1)

Total (3)

Exercise 26

Complete the following in full sentences in your homework jotter.

___________ are units of inheritance which make up chromosomes.

Chromosomes are made up of longs strands of __________ which

consists of two backbones each containing a chain of ___________

molecules. There are four types of base molecule, adenine, __________,

thymine and ______________. The ______________of the bases

determines the sequence of __________ ____________ in a protein.

Three ______ molecules form the code for one amino acid. The protein

produced controls the characteristics of the organism.

Chromosomes exist in pairs, and each normal body cell of an organism has

_______ matching sets of these. (In humans, 2 sets of ___ making ___

in total).

Total (11)

31

Exercise 27

Research report on genetic disorders

Cystic fibrosis is a medical condition that is passed from parents to their

children. This condition is caused by an error in one of the genes found in

the nucleus of the parent’s cells.

a) What are genes made of?

b) What effect might inheriting a damaged gene have on the

production of a protein?

c) Research one of the following genetic disorders. Describe how the

disorder is inherited, the symptoms and treatments. Provide a list

of references at the end.

Cystic Fibrosis

Tay-Sachs

Down’s Syndrome

Duchenne Muscular Dystrophy (DMD)

Huntington’s Disease

Exercise 28

Exam Style Questions

1. Which part of a cell controls cell division?

A Membrane

B Nucleus

C Cell wall

D Cytoplasm

2. DNA is found in which part of the cell?

A Cytoplasm

B Ribosomes

C Nucleus

D Cell membrane

32

3. The DNA of a chromosome carries information which determines the

structure and function of

A fats

B bases

C carbohydrates

D proteins

4. Which of the following is a correct description of a chromosome?

A a chain of DNA bases

B a chain of RNA bases

C a chain of amino acids

D a chain of sugar molecules

5. The DNA base, (A) adenine, pairs with what other base?

A (A) Adenine

B (T) Thymine

C (C) Cytosine

D (G) Guanine

33

6. The diagram shows DNA during replication. Base H represents

thymine (T) and base M represents guanine (G). Which letters

represent the base cytosine (C)?

A J and K

B J and L

C N and P

D N and R

7. A DNA molecule consists of 4000 bases of which 20% are adenine (A).

How many guanine (G) bases will be present in the DNA molecule?

A 800

B 1000

C 1200

D 1600

8. Decide if each of the following statements about DNA and the

34

Key Area 1.5 - Proteins and Enzymes

Exercise 29

1. All enzymes are composed of

A carbohydrates

B protein

C glycerol

D fatty acids

1

2. The enzyme phosphorylase was added to a 2% glucose-1-phosphate

solution.

After one hour, the concentration of glucose-1-phosphate had fallen to

0.05%.

How many times lower was the concentration after one hour than at the

start?

A 0.1

B 1.95

C 40

D 0.75 1

3. Two grams of fresh liver was added to hydrogen peroxide

The time taken to collect 10cm3 of oxygen foam was 2 minutes.

The rate of oxygen production was

A 2.5 cm3/g/min B 5.0 cm3/g/min

C 10.0 cm3/g/min D 20.0 cm3/g/min 1

35

4. Two grams of fresh liver was added to hydrogen peroxide at different

pH values.

The time taken to collect 10 cm3 of oxygen foam was noted for each pH.

pH of hydrogen

peroxide solution

Time to collect 10 cm3

of oxygen foam (s)

5 120

7 30

9 50

11 85

At pH 7, the enzyme which breaks down hydrogen peroxide is

A at its optimum activity

B at its minimum activity

C denatured

D digested 1

36

5. The graphs below show the effects of temperature and pH on the

activity of

enzyme.

Which line in the table identifies correctly the conditions at which the

enzyme is most active?

1

Temperature pH

A 40 2

B 40 4

C 50 2

D 60 4

37

6. Which of the graphs below shows the effect of increasing

temperature on enzyme activity? 1

A

B

C

D

38

Questions 7, 8 and 9 refer to the information below.

An investigation into the effect of pH on the digestion of milk by an

enzyme was carried out.

Five identical dishes were set up with wells cut out of the agar.

To each well was added 5 cm3 of the enzyme kept at a different pH as

shown in the diagram below.

The dishes were kept at 35°C.

The diameter of the area cleared by the action of the enzyme was

measured.

pH

Diameter of clear zone (mm)

Dish 1 Dish 2 Dish 3 Dish 4 Dish 5

1 0 0 0 0 0

3 2 1 1 2 1

5 3 4 2 3 3

7 6 5 5 5 4

9 2 2 3 1 2

11 1 0 0 1 0

39

7. The average diameter cleared at pH 5 was

A 3mm

B 4mm

C 5mm

D 6mm 1

8. The variable altered in this investigation was

A temperature

B diameter of the well

C pH

D milk concentration 1

9. The pH at which the enzyme was most active was

A 3

B 5

C 7

D 9

1

40

10. Potatoes store carbohydrate in the form of starch.

An enzyme found in potato cells converts glucose-1-phosphate into

starch.

glucose-1-phosphate Enzyme

starch

The following description outlines how an investigation into the

time taken for the synthesis of starch to occur was carried out.

1. A starch-free potato extract was prepared.

This potato extract contained the enzyme.

2. Two rows of a spotting tile were set up as shown in the

diagram.

A glucose-1-phosphate + potato

extract

B B glucose-1-phosphate + water

3. A stop clock was started.

4. Iodine was added to each column at 5 minute intervals.

Iodine turns black when starch is present.

The results

A

B

5 10 15 20

Time (minutes)

(a) Name the enzyme present in the potato extract.

1

(b) Explain why all the starch was removed from the potato

extract before it was used in the investigation.

1

All dimples in row B stayed orange

The dimples in row A

gradually turned blue/black

41

(c) What evidence is there to show that the enzyme is

necessary for the synthesis of starch?

1

(d) What conclusion can be drawn from the results in row A?

1

11. Yeast cells contain the enzyme catalase which breaks down hydrogen

peroxide into oxygen and water.

hydrogen peroxide catalase

oxygen + water

The following diagram and description outlines how an

investigation was set up and carried out.

After ten minutes in the water bath at 25oC, the yeast suspension was

mixed with the hydrogen peroxide by shaking the test tube.

The volume of oxygen released from the hydrogen peroxide in one minute

was measured.

The procedure was then repeated at 25oC.

The same apparatus was then used to investigate the effect of a range of

temperatures.

42

(a) In this investigation temperature is the only variable which should

be changed.

State two variables which should be constant. 1

(b) (i) Explain why the procedure was repeated at each

temperature and

an average calculated. 1

(ii) Explain why the yeast and hydrogen peroxide were not mixed

before

they were placed in the water bath. 1

(c) The results are shown in the table below.

Present the results in an appropriate format on a graph.

3

(19)

Temperature

(oC)

Volume of oxygen collected (cm3/minute)

First run Second run Average

25 15 15 15

30 20 22 21

35 36 40 38

40 46 46 46

45 10 8 9

50 0 0 0

60 0 0 0

43

Exercise 30

1. An experiment was set up to investigate the effect of pH on the action

of

the enzyme salivary amylase.

After 30 minutes a sample from each test tube was tested for the

presence of simple sugars.

(a) Other than temperature, state two variables that must

be kept constant in the experiment.

1

(b) The results obtained are shown in the table below.

(i) What conclusions can be drawn from these results?

1

pH Simple sugars test

1 negative

4 negative

7 positive

10 negative

44

(ii) Predict the results if the enzyme had been boiled

before use. Give an explanation for your answer.

1

(c) Explain why food containing starch must be digested before

it can be used in the human body.

1

2. (a) Four groups of students investigated the catalase concentration

of different tissues.

Each group set up a test tube containing 5 cm3 of hydrogen

peroxide and a cube of potato. The oxygen was collected over a 3

minute period and the volume was measured as shown in the

diagram below.

This procedure was repeated by each group using cubes of liver,

apple and carrot.

Tissue

Volume of oxygen collected in 3 minutes (cm3)

Group 1 Group 2 Group 3 Group 4 Average

Potato 5.5 5.0 5.5 6.0

Liver 39.5 37.0 42.5 35.5 38.5

Apple 1.0 1.5 1.0 0.5 1.0

Carrot 3.5 3.0 3.5 2.0 3.0

45

(i) Copy and complete the table to show the average volume of

oxygen collected for potato tissue.

1

(ii) The volume of hydrogen peroxide and time to collect the

oxygen were kept constant in this investigation.

State two other variables that must be kept constant. 1

(iii) What was done in this investigation to make the results

reliable? 1

(iv) What conclusion can be drawn from these results? 1

3. (b) The diagram below shows the action of the enzyme

phosphorylase in a potato.

(i) Copy the following sentence and select the option to make

the sentence correct.

The action of the enzyme phosphorylase catalyses the

syntheses / degradation of starch.

1

(ii) State the effect of phosphorylase on the rate of this

reaction. 1

(iii) Explain why lipase could not produce starch in this reaction.

1

46

4. The leaves of black walnut trees produce a chemical which is released

into the soil when the leaves fall. This chemical prevents the germination

(growth) of other plant seeds. The chemical can be extracted from the

leaves.

(a) A student carried out an investigation into the effect of this

chemical on mung bean seeds. Leaf extracts containing

different concentrations of the chemical were prepared.

The student was supplied with:-

30 mung bean seeds a bottle of 0.1% leaf extract chemical

3 identical petri dishes a bottle of 1% leaf extract chemical

cotton wool a bottle of 10% leaf extract chemical

(i) Copy and complete the diagrams below to show how the

investigation should have been set up. Label the contents

of each petri dish.

2

(ii)

Petri dish 1 Petri dish 2 Petri dish 3

(iii) What observations and measurements should be taken to

obtain results for this investigation?

1

(iv) A control Petri dish should also have been set up to show

that it was the leaf extract preventing the growth of the

mung bean seeds.

Copy and complete the diagram below to show the

contents of the control Petri dish.

1

Control Petri dish

cotton

wool

cotton

wool

cotton

wool

cotton

wool

47

(b) Explain why producing this chemical is an advantage to the

blackwalnut trees.

1

5. (a) Enzymes are involved in synthesis or degradation chemical

reactions.

The diagram below represents an example of one of these types of

reactions.

(i) Name the type of chemical reaction and the enzyme shown in the

diagram. 1

(ii) Copy the diagram and place an X to show the position of an active

site. 1

(b) What type of molecule are all enzymes made of?

1

(c) What happens to the active site when an enzyme is denatured?

1

(d) State the effect of an enzyme on the energy input needed for

chemical reaction.

1

(21)

48

Exercise 31

1. Albumin is a protein that can be broken down by the enzyme trypsin.

When albumin is added to agar the agar becomes cloudy.

When the albumin is broken down by trypsin the agar becomes clear.

albumin sintryp

amino acids

Groups of students carried out an investigation to find the effect on

pH on the activity of the enzyme trypsin.

Each group carried out the following procedure.

1. A petri dish containing cloudy albumin agar was collected.

2. Three wells were cut out of the agar.

3. Drops of trypsin and buffer solution of different pH were

added to the wells as shown in the diagram below.

cloudy albumin trypsin and buffer at

pH4

agar

trypsin and trypsin and buffer at

pH7

buffer at pH9

4. The dishes were incubated at 37oC for 24 hours.

5. The diameter of the clear zone around each well was

measured.

49

(a) State one variable that should have been kept constant

when the dishes were set up.

1

(b) The results from each group are given in the table below.

(i) Copy and complete the table by calculating the average diameter of

the clear area for pH7.

1

(ii) Explain why the results for all groups were collected and averages

calculated.

1

(iii) From the results describe the effect of pH on the activity of

trypsin.

1

(c) The group suggested setting up a control to show that the

enzyme caused the observed effects.

Copy and complete the labels on the diagram below to show the content of

the wells for the control.

cloudy albumin

agar

pH

Diameter of the clear area (mm)

Group 1 Group 2 Group 3 Group 4 Average

4 1 2 0 3 1.5

7 6 9 8 11

9 21 23 20 24 2.2

50

1

2. (a) Amylase is produced in the salivary glands. The substrate of

amylase is

starch.

Amylase was added to a starch suspension and a sugar was

produced.

(i) Name the sugar produced by the action of amylase on starch.

1

(ii) State the optimum oC temperature for the action of amylase.

1

(b) An enzyme has a shape which is complementary to its

substrate.

(i) What term describes this property of an enzyme?

1

(v) Name the part of the enzyme that is complementary to its

substrate.

1

3. The diagram below represents an amylase molecule.

51

Describe and explain the events that take place when the enzyme is

added to a starch suspension.

3

(12)

Key Area 8 - Photosynthesis

Exercise 9 1. Groups of students carried out an investigation into the effects of

competition.

Trays containing seeds were set up as shown below.

The trays were watered regularly to allow germination to take

place.

After several days the seedlings were observed and the number

with healthy green leaves was noted.

The results are shown in the table below.

Number of seeds in

Number of seedlings with

Percentage of seedlings with

52

each tray healthy green leaves

healthy green leaves

15 12 80

30 18 60

45 23 51

60 24 40

(i) Predict the percentage of seedlings with healthy green

leaves if

75 seeds were sown in a seed tray.

1

(ii) State two factors for which the seedlings could be

competing in this investigation.

1

2. (a) An experiment was set up to measure the effect of light intensity

on the

rate of photosynthesis in the water plant. Elodea.

The light intensity was varied using a dimmer switch on the bulb.

The rate of photosynthesis was measured by counting the number

of bubbles released per minute.

53

(i) Name the gas collected.

1

(ii) The results of the experiment are shown in the table

below.

(a) On a grid, plot a line graph to show rate of photosynthesis against

light intensity.

2

(b) Using the data in the table, explain the results obtained at light

intensities greater than 8 units.

1

3. (a) There are two reactions in photosynthesis. The first reaction is

photolysis.

(i) Name the two substances produced by photolysis that

are

required for the second reaction.

1

Light intensity (units)

Rate of photosynthesis (number of bubbles per minute)

1 2

3 10

5 23

8 45

10 45

12 45

54

(ii) Name the second reaction.

1

(b) Plant cells convert glucose into other carbohydrates.

Copy and complete the table below by naming two of these

carbohydrates.

2

4. The rate of photosynthesis is limited by certain environmental

factors.

Name two limiting factors and describe how the growth of

greenhouse plants in winter can be increased.

3

Items 5 and 6 refer to the accompanying diagram which shows some of

the steps carried out to test a leaf for the presence of starch.

5. The correct sequence of the steps is 1

A Y, W, Z, X

B Z, W, Y, X

C Y, W, X, Z 1

D Z, Y, W, X

6. The reason for carrying

out step W is to 1

A kill the leaf cells

B soften the leaf discs

C remove chlorophyll from

the leaf cells

Role of carbohydrate in plant cells

Name of carbohydrate

Storage as an insoluble material

Forms cell walls

55

D extract oxygen bubbles

from the leaf discs

Items 7 and 8 refer to the accompanying diagram. The plant was left in

sunlight for two days and then leaf discs W, X, Y and Z were tested for

the presence of starch.

7. The leaf disc found to contain starch was

A W

B X

C Y 1

D Z

8. This experiment proves that in order to photosynthesise, a plant must

have

A sunlight and carbon dioxide

B carbon dioxide and water

C chlorophyll and sunlight 1

D carbon dioxide and chlorophyll

56

9. A variegated leaf on a destarched ivy plant was treated as shown in

the

accompanying diagram.

Which of the following shows the appearance of the leaf after testing

it for

starch?

1

10. The total volume of carbon dioxide daily entering the plant shown in

the

accompanying diagram is 24 000 mm3.

The daily rate of diffusion of carbon dioxide into the plant in mm3

CO2 per

mm2 of leaf is

57

A 0.16 1

B 6.00

C 48.00

D 3000.00

Questions 11 and 12 refer to the accompanying diagram which shows the

process of photolysis. The two questions also refer to the following

possible answers.

A water

B oxygen 1

C hydrogen

D carbon dioxide

11. What is the correct identity of

chemical substance X? 1

12. What is the correct identity of

chemical substance Y? 1

13. Which of the following CANNOT be used to measure rate of

photosynthesis? 1

A volume of oxygen released per unit time

B volume of carbon dioxide taken up per unit time

C mass of carbohydrate produce per unit time

D volume of water vapour released per unit time

58

14. The graph in the accompanying diagram shows the

results from a photosynthesis experiment. 1

Which of the following pairs of environmental factors

must be kept constant during this experiment to make

it valid?

A light intensity and temperature

B Temperature and carbon dioxide concentration

C water content and oxygen concentration

D light intensity and carbon dioxide concentration

(24)

Exercise 10

1. Products of the photolysis stage of photosynthesis are

A glucose and hydrogen

B carbon dioxide and hydrogen

C water and oxygen 1

D hydrogen and oxygen

2. Which of the following are all limiting factors in photosynthesis?

A Carbon dioxide concentration, temperature and light

intensity.

B Carbon dioxide concentration, oxygen concentration and light

intensity.

C Oxygen concentration, temperature and light intensity. 1

D Oxygen concentration, carbon dioxide concentration and

temperature.

59

3. Which line in the table below identifies the best conditions for the

production of early crops?

1

4. What must be present in leaf cells for photosynthesis to take

place?

A carbon dioxide and water

B oxygen and water

C carbon dioxide and oxygen

1

D oxygen and hydrogen

5. The word

equation for

photosynthesis is

A carbon dioxide + water glucose + oxygen

B oxygen + water glucose + carbon dioxide 1

C glucose + oxygen carbon dioxide + water

D carbon dioxide + oxygen glucose + water

Added factor Light intensity

A oxygen high

B oxygen medium

C carbon dioxide medium

D carbon dioxide high

60

6. Plants compete mainly for

A water, light and soil nutrients

B water, food and soil nutrients 1

C light, water and food

D light, food and soil nutrients

7. ATP synthesised during photolysis provides the carbon fixation

stage of photosynthesis with

A glucose

B carbon dioxide

C energy

1

D hydrogen

8. Photolysis is the

A combining of water with carbon dioxide

B use of water by chlorophyll to split light

C release of energy from water using light energy 1

D splitting of water using light energy

9. The table below shows the rate of photosynthesis by a plant

measured at different light intensities.

Light intensity (kilolux)

Rate of photosynthesis (units)

10 2

61

What change in light intensity produces the greatest increase in

the rate of photosynthesis?

An increase in light intensity from

A 10 to 20 kilolux 1

B 20 to 30 kilolux

C 30 to 40 kilolux

D 40 to 50 kilolux

20 27

30 51

40 73

50 82

62

10. The bar chart below shows the number of cells of different

lengths in a sample of onion epidermis.

The percentage of cells with a length greater than 55 micrometres

is

A 10%

B 15% 1

C 20%

D 30%

11.. The diagram below shows an investigation into photosynthesis.

Number of cells

Length of cell (micrometres)

63

Which of the following statements is correct?

A P, Q and R make food

B only P and Q make food

C only P makes 1

D only R makes food

12. The diagram below shows the carbon fixation stage of

photosynthesis.

Which line in the table correctly identifies X and Y?

X Y

A hydrogen starch

B starch ADP

ATP X

carbon dioxide glucose Y

64

1

13. The graph below shows the effect of increasing light intensity on

the rate of photosynthesis.

Light intensity (units)

Which factor is limiting the rate of photosynthesis at point X on

the graph?

A carbon dioxide concentration

B temperature

C light intensity 1

D oxygen concentration

C starch oxygen

D water starch

Rate of

photosynthesis

(bubbles of

oxygen

released per minute)

65

14. The graph below shows the effect of temperature on the rate of

photosynthesis in a plant.

Rate of

photosynthesis

10 15

Temperature (oC)

A correct conclusion would be that

A as the temperature increases, the rate of photosynthesis

increases

B as the temperature increases, the rate of photosynthesis

decreases

C as the temperature increases, the rate of photosynthesis

remains constant

D as the temperature decreases, the rate of photosynthesis

1 increases

15. The following stages occur during photosynthesis.

W glucose is formed

X water is broken down to produce hydrogen

Y glucose is converted to starch

Z hydrogen is combined with carbon dioxide

The correct order for these stages is

A W Z X Y

B Z Y X W

66

C X Z W Y

D Y X Z W 1

67

16. An experiment was carried out to investigate the growth of pea

plants kept in a high light intensity following germination.

The graph shows the average shoot length of the pea plants.

During which 5 day period is there the greatest increase in average

shoot length?

A Day 10 – 15

B Day 15 – 20 1

C Day 20 – 25

D Day 25 – 30

68

17. The diagram below shows the internal structure of a leaf.

During the hours of daylight, the concentration of carbon dioxide

in the air spaces is higher than in the cells of layer X.

Explain why this difference in concentration is important to the

leaf cells.

3

69

18. The rates of photosynthesis and respiration in a green plant were

measured over a period of 24 hours.

The results are shown in the graph below.

(a) At what time was the production of glucose at its

maximum?

1

(b) Between what two times was the plant producing more

oxygen than it was using?

1

(c) What substance traps the light energy required for

photosynthesis? 1

(d) The diagram below represents a summary of part of the

process of photosynthesis.

Reaction

X

Name the following:

Key

photosynthesis

respiration

ATP + hydrogen

Substance Y glucose

Substance Z

(structural

component of

cell walls?

70

Reaction X; Substance Y; Substance Z

2

(24)

Exercise 11

1. a) Lettuces may be grown in ‘tunnels’ covered in clear polythene as

shown in

the diagram below.

Air rich in carbon dioxide can be passed through these tunnels.

Explain how this would make lettuces grow faster.

2

b) The graph below shows how the rate of photosynthesis is affected

by

light intensity at different concentrations of carbon dioxide.

71

(i) What factor was limiting the rate of photosynthesis at points 1 and

2? 2

(ii) Name one other factor that may limit the rate of photosynthesis. 1

2. a) A scientist grew some cereal plants in a field.

During the course of the day, she removed 2 plants every 4 hours and

measured the concentrations of sugar in the leaves of the plants.

The results are shown in the table below.

Sugar concentration (percentage of dry mass)

Time of day (hours)

Sample 1 Sample 2 Average

0400 0.42 0.48 0.45

0800 0.58 0.62 0.60

1200 1.46 2.04 1.75

1600 1.57 2.43 2.00

2000 1.05 1.75 1.40

2400 0.49 0.51 0.50

72

Present the results in an appropriate format on a grid. (3)

(b) The following word equation shows the first stage of

photosynthesis.

water oxygen + hydrogen + ATP

(i) Name this stage of photosynthesis.

1

(ii) Describe what happens to each of the following

products.

(a) Oxygen

1

(b) Hydrogen

1

(c) ATP

1

3. (a) Some students were asked to design an investigation to

compare the rate of production of oxygen gas by two

different species of

water plant.

The diagrams below show the proposed procedure.

light energy

73

Identify two changes to the procedure that should be made

to ensure that a valid conclusion can be made.

2

(b) When changes were made to ensure validity, the following

results were obtained.

(i) Calculate the rate of oxygen production for Plant Q.

1

(ii) Calculate the ratio of oxygen produced by Plant P to

that

produced by Plant Q.

1

(c) The volume of oxygen produced was measured at time

intervals of one minute.

The results for Plant Q are shown in the line graph below.

Plant Total volume of

oxygen produced in8 minutes (cm3)

Rate of oxygen production

(cm3/minute)

P 64 8

Q 96

74

Describe what happens to the volume of oxygen produced per

minute as the investigation proceeds.

1

(d) The diagram below shows the first stage of photosynthesis.

light energy

Stage 1

water

hydrogen oxygen

(i) Name the substance which captures the light energy needed

at Stage 1.

1

(ii) The energy is used to split water molecules.

1

What name is given to this process?

1

75

(iii) The hydrogen the combines with carbon dioxide to form

glucose.

Name this second stage in photosynthesis.

1

4. (a) A horticulturist grew a crop of peas in a polythene tunnel.

State two conditions that could limit the rate of

photosynthesis in the pea plants. 1

(b) The graph below shows the mass of sugar in the leaves and the

concentration of carbon dioxide just above the pea plants at

different times of the day.

concentration of carbon dioxide above the leaves

mass of sugar in the leaves

(i) For how many hours did the carbon dioxide concentration

decrease

76

(ii) Explain this decrease in carbon dioxide concentration.

2

(iii) Explain why the mass of sugar in the leaves is as its

maximum at

1600.

1

(iv) Calculate the percentage increase in sugar in the leaves

between 0400 and 1600.

1

(v) Give two reasons why the mass of sugar decreases between

2000 and 0000.

1

5. Groups of students carried out an investigation into the effects of

competition.

Trays containing seeds were set up as shown below.

The trays were watered regularly to allow germination to take

place.

After several days the seedlings were observed and the number

with healthy green leaves was noted.

The results are shown in the table below.

Number of seeds in

each tray

Number of seedlings with healthy green

leaves

Percentage of seedlings with healthy green

leaves

15 12 80

77

30 18 60

45 23 51

60 24 40

(i) Predict the percentage of seedlings with healthy green

leaves if 75 seeds were sown in a seed tray.

1

(ii) State two factors for which the seedlings could be

competing in this investigation.

1

6. Groups of students carried out an investigation into the effects of

competition.

Trays containing seeds were set up as shown below.

The trays were watered regularly to allow germination to take

place.

After several days the seedlings were observed and the number

with healthy green leaves was noted.

The results are shown in the table below.

78

Number of seeds in

each tray

Number of

seedlings with

healthy green

leaves

Percentage of

seedlings with

healthy green

leaves

15 12 80

30 18 60

45 23 51

60 24 40

(i) Predict the percentage of seedlings with healthy green

leaves if 75 seeds were sown in a seed tray.

1

(ii) State two factors for which the seedlings could be

competing in this investigation.

1

(30)

Key Area 7 - Respiration

Exercise 7

1. Which of the following shows the use of energy released from the

breakdown

of glucose?

A ATP + Pi ADP

B ADP + Pi ATP

C ATP ADP + Pi 1

79

D ADP ATP + Pi

2. The energy values of different food materials are shown on the table.

How much energy is contained in a food sample consisting of 3

grams of glucose and 2 grams of fat?

A 17 kJ

B 21 kJ 1

C 30 kJ

D 35 kJ

3. The diagram below shows energy transfer within a cell.

Food Energy value (kJ per gram)

Glucose 4

Protein 4

Fat 9

80

Which line of the table below identifies correctly compounds X

and Y?

1

4. (a) The diagram below shows part of an investigation into the effect

of

adding three different concentrations of ATP solution to three

pieces of

muscle.

X Y

A glucose ATP

B glucose ADP

C ADP ATP

D ATP glucose

81

Equal volumes of the ATP solutions were added to the pieces of

muscle.

The results are shown in the following table.

(i) Calculate the percentage decrease in length of the

muscle

with 10 g per litre ATP solution.

Copy and complete the table. 1

(ii) In this experiment why is it necessary to use

percentage

Concentration of ATP solution

(g per litre)

Length of muscle

At start (mm)

After 10 minutes

(mm)

Decrease (mm)

Percentage decrease

1 35 34.3 0.7 2

5 50 46 4 8

10 40 33 7

82

decrease in length in the comparison of the results?

1

(iii) Explain why three different syringes should be used in

this

investigation.

1

5. The diagram below shows the apparatus used to investigate the energy

content of different foods. One gram of each food was burned under

a

beaker containing 100 cm3 of water.

The temperature rise for each food was recorded.

The energy content of the foods was calculated using the

following

equation.

energy content = temperature rise x 420 (joules/g)

The table below shows the results for the investigation.

Food Energy value (joules/g)

83

(a) Calculate the simple whole number ratio of the energy content

of

chicken to that of butter. 1

(b) Construct a bar graph of the results in the table.

2

(c) One gram of fish was also burned. The temperature rise was

7.5oC.

Calculate the energy content for fish using the equation above.

1

(d) Slimmers may be advised to use margarine instead of butter. Use

the data in the table to suggest why this would not aid weight

loss. 1

6. The diagram below shows the main stages of aerobic respiration.

Glucose

Stage 1

ATP

Pyruvate

Stage 2

X

Hydrogen

butter 10500

chicken 4200

bread 3400

margarine 10500

84

Water

ATP Y

(a) Name Stage 1.

1

(b) Name substances X and Y.

2

(c) Which substance shown in the diagram is the source of the

energy used to synthesis ATP?

1

(d) Copy and complete the following word equation which

represents the syntheses of ATP.

1

+ + energy ATP

(e) How many molecules of ATP are produced per glucose

molecule during each of Stage 1 and Stage 2.

1

(f) During aerobic respiration some energy is lost from the cell.

In what form is this energy?

1

7. The diagram below represents an animal cell that is respiring

aerobically.

aerobic respiration

occurs in the cell

raw materials wastes leave

enter the cell the cell

85

Describe the two stages of aerobic respiration.

Include the name of the raw materials and the products of the two

stages.

3

(21)

Exercise 8

86

1. The fermentation pathway of one molecule of glucose results in the

net gain

of

A 2 molecules of ATP

B 2 molecules of ADP

C 38 molecules of ATP 1

D 38 molecules of ADP

2. The bar chart shows the volume of blood supplied per minute to the

skeletal

muscles and to other parts of the body of a healthy male at rest and

during strenuous exercise.

During exercise, the ratio of blood supplied to the muscles to

blood supplied to other parts of the body is

A 1 : 4

B 4 : 1

Key

blood to

muscles

blood to

other

parts of

the body

87

C 10 : 8

1

D 10 : 9

88

3. An investigation was carried out into the concentration of lactic acid

in the

blood before, during and after a two minute period of strenuous

exercise.

The results are shown in the graph below.

(a) What was the concentration in mg/100 cm3 of lactic acid in the

blood ten

minutes after the start of the exercise?

1

(b) Explain why the concentration of lactic acid in the blood increased

during

89

and immediately after the strenuous exercise.

1

(c) What caused the lactic acid concentration to decrease 15 minutes

after

the start of the exercise?

1

4. As part of an investigation into the effect of different solutions on

fresh

muscle tissue, 12 drops of ATP were added to a strand of fresh

muscle of

initial length 50 mm. After a few minutes it length was found to be

42 mm.

Which line in the table correctly summarises the experiment?

1

5. The rise in level of coloured liquid indicates that the

A grasshopper is taking in oxygen

B sodium hydroxide is absorbing oxygen

C grasshopper is giving out carbon dioxide 1

D sodium hydroxide is releasing carbon dioxide

6. From this experiment it can be concluded that the grasshopper’s rate

of

A carbon dioxide output is 0.2 ml/hour

% difference in length

of muscle strand

Reason for change

A 8 contraction of muscle fibres

B 8 relaxation of muscle fibres

C 16 contraction of muscle fibres

D 16 relaxation of muscle fibres

90

B carbon dioxide output is 4.0 ml/hour

C oxygen consumption is 2.0 ml/hour 1

D oxygen consumption is 0.4 ml/hour

Items 7 and 8 refer to the accompanying diagram which represents the

process of the fermentation pathway in plant cells.

7. The number of molecules of ATP formed at position X following the

breakdown of one molecule of glucose is

A 2

B 18

C 36 1

D 38

8. The substance released at position Y is

A water

B oxygen 1

C hydrogen

D carbon dioxide

Questions 9, 10, 11 refer to the accompanying graph which shows the

effect

of a period of exercise followed by a period of rest on the lactic acid

concentration of the blood of a healthy fit teenager.

9. For how many minutes did the period of exercise last?

A 6

B 10 1

C 12

D 14

10. How many minutes did it take for the

concentration of lactic acid to drop from

its highest level to 50% of its highest

91

level?

A 19

B 20 1

C 38

D 40

11. If the trend at X continues, at what time

will the initial level of lactic acid in the

blood be reached?

A 15.56

B 16.02

C 16.08 1

D 16.20

Items 12 and 13 refer to the data in the following table which were

obtained from a series of experiments involving a group of 18 year olds.

Activity Average rate of

oxygen consumption

(cm3/s)

Average rate of energy

consumption (kJ/min)

Cycling 21 26

Swimming 23 28

Skiing 26 33

Brick-laying 29 36

12. From the data it can be concluded that the average rate of oxygen

consumption is

A inversely related to CO2 output

B greatest for sporting activities 1

C directly related to energy consumption

D inversely related to energy released as heat

13. Which pair of bars in the accompanying graph

92

represents skiing?

1

14. During jogging, a 16 year old was found to use 40 kJ per minute. The

energy

for 15 minutes of this activity could be supplied by consuming 50g of

one of

the foods in the accompanying table. Which one?

1

15. Which of the following would NOT affect the daily energy

requirement of a

5 year old child?

A the climate in which the child lives

Food Energy content (kJ/g)

A honey 12

B sucrose 19

C biscuit 21

D chocolate 24

93

B the height of the child

C the weight of the child

D the sex of the child 1

16. The energy released during the breakdown of ATP is NOT used for

A synthesis of protein

B transmission of nerve impulses

C production of enzymes

D digestion of fats 1

17. Which of the following equations correctly represents muscular

action?

1

18. Which substance would be produced by skeletal muscle fibres

respiring in

the absence of oxygen? 1

(20)