Cambridge International Examinations

Cambridge International General Certificate of Secondary Education

BIOLOGY 0610/23
Paper 2 Multiple Choice (Extended) May/June 2017
45 minutes
Additional Materials: Multiple Choice Answer Sheet
*3291229666*

Soft clean eraser

Soft pencil (type B or HB is recommended)

READ THESE INSTRUCTIONS FIRST

Write in soft pencil.

Do not use staples, paper clips, glue or correction fluid.
Write your name, Centre number and candidate number on the Answer Sheet in the spaces provided
unless this has been done for you.
DO NOT WRITE IN ANY BARCODES.

There are forty questions on this paper. Answer all questions. For each question there are four possible
answers A, B, C and D.
Choose the one you consider correct and record your choice in soft pencil on the separate Answer Sheet.

Read the instructions on the Answer Sheet very carefully.

Each correct answer will score one mark. A mark will not be deducted for a wrong answer.
Any rough working should be done in this booklet.
Electronic calculators may be used.

The syllabus is approved for use in England, Wales and Northern Ireland as a Cambridge International Level 1/Level 2 Certificate.

This document consists of 16 printed pages.

IB17 06_0610_23/2RP
© UCLES 2017 [Turn over
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1 Which characteristic do all living organisms show?

A breathing
B excretion
C photosynthesis
D tropism

2 The diagram shows some animal cells, as seen under the microscope.

What will be present at X?

A one cell membrane

B one cell wall
C two cell membranes
D two cell walls

3 Which structures are present in large numbers in cells with high rates of metabolism?

A chromosomes
B mitochondria
C ribosomes
D vacuoles

© UCLES 2017 0610/23/M/J/17

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4 The diagram shows a section through a root.

P
Q

What are the levels of organisation of the labelled structures?

cell organ tissue

A P Q R
B P R Q
C Q R P
D R Q P

5 Which characteristics are correct for both osmosis and diffusion?

require a partially require a are energy

permeable membrane concentration gradient consuming processes

A ✓ ✓ ✗
B ✓ ✗ ✓
C ✗ ✓ ✗
D ✗ ✗ ✓

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6 The bases on one of the strands of a DNA molecule have the sequence shown.

A-A-T-C-T-G

What is the corresponding sequence of bases on the other strand?

A A-A-T-C-T-G
B C-C-G-A-G-T
C G-G-C-T-C-A
D T-T-A-G-A-C

7 Which statement describes the effect of temperature on enzymes?

A High temperatures denature enzymes making it difficult for substrate molecules to fit into the
active site.
B High temperatures denature enzymes making it easy for substrate molecules to fit into the
active site.
C Low temperatures denature enzymes making it difficult for substrate molecules to fit into the
active site.
D Low temperatures denature enzymes making it easy for substrate molecules to fit into the
active site.

8 Four test-tubes are set up as shown.

Which test-tube contains the most carbon dioxide after one hour?

A B C D

black
water polythene
to keep
water out light
snail light light light
aquatic
plant

© UCLES 2017 0610/23/M/J/17

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9 The diagrams show the structure of four different cells from the leaf of a dicotyledonous plant.

Which cell is a guard cell?

A B

NOT TO
SCALE

C D

10 Which mineral ion is absorbed by plant roots and used in the production of all amino acids?

A carbonate
B hydroxide
C magnesium
D nitrate

11 Which is the equation for photosynthesis?

A C6H12O6 → 2C2H5OH + 2CO2

B C6H12O6 + 6O2 → 6CO2 + H2O

C 2C2H5OH + 2CO2 → C6H12O6

D 6CO2 + 6H2O → C6H12O6 + 6O2

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12 Statements 1– 4 describe stages in the development of cholera.

1 Chloride ions are secreted in the gut.

2 Osmosis causes water to move into the gut.
3 The infected person becomes dehydrated.
4 Toxins are produced by the pathogenic bacteria.

What is the correct sequence of the four stages?

A 1→2→3→4

B 1→4→3→2

C 4→1→2→3

D 4→1→3→2

13 The diagram shows a person’s teeth. Some of their teeth are missing.

What would the person find difficult?

A biting apples
B drinking water
C grinding meat
D tearing dry bread

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14 The graph shows the effect of pH on the activity of three different enzymes.

Z
X Y

enzyme
activity

0 2 4 6 8 10
pH

The table shows the pH of different parts of the alimentary canal.

part of the
pH
alimentary canal

mouth 7.0
stomach 2.0
small intestine 8.5

Which enzymes in the graph are likely to be protease enzymes?

A X, Y and Z B X and Z only C Y and Z only D Z only

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15 The diagram shows a villus. Structures P and Q absorb different products of digestion.

P
Q

Which row identifies the products absorbed by P and Q?

P Q

A amino acids glucose

B fatty acids maltose
C glucose fatty acids
D maltose amino acids

16 The diagram shows a leaf attached to the stem of a plant.

sunlight

What do the arrows at X represent?

A movement of amino acids in phloem

B movement of carbon dioxide in phloem
C movement of mineral ions in xylem
D movement of sucrose in xylem

© UCLES 2017 0610/23/M/J/17

 9

17 Which row shows what is carried, and in which direction, by the pulmonary vein?

what is carried direction

A deoxygenated blood from the heart

B deoxygenated blood to the heart
C oxygenated blood from the heart
D oxygenated blood to the heart

18 Which component of the blood produces antibodies?

A lymphocytes
B phagocytes
C plasma
D red blood cells

19 Which statement about antibodies is correct?

A Breast milk contains antibodies and protects babies by giving them active immunity.
B Injections of antibodies give passive immunity against the disease scurvy.
C Insect repellents contain antibodies and give mosquitoes passive immunity against malaria.
D Injections of antibodies give passive immunity against some pathogens.

20 Which row shows the correct combination of muscle contractions and the pressure in the thorax
when breathing out?

internal external
pressure
intercostal intercostal diaphragm
in thorax
muscles muscles

A contracted contracted contracted high

B contracted relaxed relaxed high
C relaxed contracted contracted high
D relaxed relaxed relaxed low

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21 Which is not involved in removing the oxygen debt after a human has been exercising?

A aerobic respiration of alcohol in the liver

B aerobic respiration of lactic acid in the liver
C continuation of deeper breathing
D continuation of faster heart rate

22 A longitudinal section of the kidney and some associated structures have been labelled.

Which labelling is correct?

A B

cortex cortex

renal artery renal vein

ureter ureter
medulla medulla

C D

medulla medulla

renal artery ureter

ureter renal artery

cortex cortex

© UCLES 2017 0610/23/M/J/17

 11

23 The diagram shows a synapse.

What do the dots at X represent?

A neurotransmitter
B receptor molecule
C synaptic cleft
D vesicle

24 Which is the light sensitive part of the eye?

A cornea
B iris
C lens
D retina

25 What is meant by the term phototropism?

A absorbing mineral ions using light energy

B directional growth in response to gravity
C directional growth in response to light
D making food using light energy

26 Which row shows the effects of excessive alcohol consumption?

anti-social
reaction time self-control
behaviour

A quicker increased increased

B quicker reduced increased
C slower increased decreased
D slower reduced increased

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27 Dianthus flowers can be one of three different colours: red, pink or white.

A red flower is always homozygous and a white flower is always homozygous. Pink flowers are
heterozygous.

If a red and a white flower are crossed, what percentage of the offspring will be pink?

A 0% B 25% C 75% D 100%

28 The diagram shows the ovary of a flower.

pollen grain

ovary

Which process is shown in the diagram?

A cross-pollination
B fertilisation
C meiosis
D self-pollination

29 What is a function of the placenta?

A a barrier to nicotine
B a barrier to the rubella virus
C exchange of blood
D transfer of dissolved nutrients

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30 Some men do not produce healthy sperm cells. A couple may choose to use the sperm of
another man, a donor, in order for the woman to get pregnant.

Which procedure involves inserting sperm into the vagina of a woman from a donor?

A artificial insemination (AI)

B birth control
C in vitro fertilisation (IVF)
D vasectomy

31 Which blood component is destroyed in people who are HIV positive?

A lymphocytes
B phagocytes
C platelets
D red blood cells

32 Four of the processes involved in the production of a protein are shown.

1 mRNA attaches to a ribosome.

2 mRNA moves to the cytoplasm.
3 The ribosome assembles amino acids into a protein molecule.
4 An mRNA copy of the gene is made.

In which sequence do these events normally occur?

A 1→2→3→4

B 2→1→3→4

C 4→2→1→3

D 4→3→2→1

33 Which statement about the sex chromosomes is correct?

A Men and women can inherit characteristics from genes carried on the X chromosome.
B Men and women can inherit characteristics from genes carried on the Y chromosome.
C Only men can inherit characteristics from genes carried on the X chromosome.
D Only women can inherit characteristics from genes carried on the Y chromosome.

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34 Which row best describes human blood groups?

has no shows shows

affected by
intermediate continuous discontinuous
environment
phenotypes variation variation

A ✓ ✗ ✓ ✗
B ✓ ✗ ✗ ✓
C ✗ ✓ ✓ ✗
D ✗ ✓ ✗ ✓

35 The diagram represents part of an aquatic food web.

tadpoles
water
beetles
aquatic
plants
fish
small
shrimps
frogs

Which organisms are primary consumers in this food web?

A small shrimps and tadpoles

B tadpoles and frogs
C water beetles and fish
D water beetles and frogs

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36 The diagram shows part of the water cycle.

clouds

T
air

S plants water in soil

rivers and lakes

What are processes S and T?

S T

A condensation drainage
B condensation evaporation
C evaporation precipitation
D evaporation transpiration

37 The graph shows the changes in the populations of predator and prey over a period of time.

Which point on the graph shows a decrease in predator population?

A
C
number of
individuals

D
B

time

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38 Which is an example of genetic engineering?

A altering the DNA in crop plants so they are resistant to herbicides

B only breeding from crop plants that are resistant to insect pests
C production of insulin in the pancreas
D using yeast to produce ethanol for biofuels

39 Why is yeast used in breadmaking?

A to produce alcohol
B to produce carbon dioxide
C to use up oxygen
D to use up sugar

40 The graph shows the levels of dissolved oxygen and mineral ions in a river.

At which point does raw sewage enter the river?

direction of river flow

dissolved oxygen

levels

mineral ions

A B C D

distance along river

Permission to reproduce items where third-party owned material protected by copyright is included has been sought and cleared where possible. Every
reasonable effort has been made by the publisher (UCLES) to trace copyright holders, but if any items requiring clearance have unwittingly been included, the
publisher will be pleased to make amends at the earliest possible opportunity.

To avoid the issue of disclosure of answer-related information to candidates, all copyright acknowledgements are reproduced online in the Cambridge
International Examinations Copyright Acknowledgements Booklet. This is produced for each series of examinations and is freely available to download at
www.cie.org.uk after the live examination series.

Cambridge International Examinations is part of the Cambridge Assessment Group. Cambridge Assessment is the brand name of University of Cambridge Local
Examinations Syndicate (UCLES), which is itself a department of the University of Cambridge.

© UCLES 2017 0610/23/M/J/17

 Cambridge International Examinations
Cambridge International General Certificate of Secondary Education

BIOLOGY 0610/23
Paper 2 Multiple Choice (Extended) May/June 2018
45 minutes
Additional Materials: Multiple Choice Answer Sheet
Soft clean eraser
*7539978956*

Soft pencil (type B or HB is recommended)

READ THESE INSTRUCTIONS FIRST

Write in soft pencil.

Do not use staples, paper clips, glue or correction fluid.
Write your name, Centre number and candidate number on the Answer Sheet in the spaces provided
unless this has been done for you.
DO NOT WRITE IN ANY BARCODES.

There are forty questions on this paper. Answer all questions. For each question there are four possible
answers A, B, C and D.
Choose the one you consider correct and record your choice in soft pencil on the separate Answer Sheet.

Read the instructions on the Answer Sheet very carefully.

Each correct answer will score one mark. A mark will not be deducted for a wrong answer.
Any rough working should be done in this booklet.
Electronic calculators may be used.

This syllabus is approved for use in England, Wales and Northern Ireland as a Cambridge International Level 1/Level 2 Certificate.

This document consists of 15 printed pages and 1 blank page.

IB18 06_0610_23/3RP
© UCLES 2018 [Turn over
 2

1 Which organisms carry out respiration, growth, movement and excretion?

A all animals and all plants

B animals only
C arthropods and flowering plants only
D plants only

2 The diagram shows an animal whose scientific name is Falco peregrinus.

To which species does it belong?

A bird
B F. peregrinus
C Falco
D vertebrate

3 What kind of skin do amphibians have?

A dry without scales

B dry with scales
C moist without scales
D moist with scales

© UCLES 2018 0610/23/M/J/18

 3

4 The diagram shows a flowering plant.

Use the key to identify the plant.

plant

flower has four petals flower has five petals

leaves with leaves with leaves with leaves with

smooth edges jagged edges smooth edges jagged edges

A B C D

5 In which part of the cell does aerobic respiration occur?

A cytoplasm
B mitochondrion
C ribosome
D vesicle

6 Why do some root cells have root hairs?

A for the maintenance of the temperature of the cell sap

B to increase the surface area of the cells
C to increase the volume of the cell sap
D to provide a place for cell nuclei

© UCLES 2018 0610/23/M/J/18 [Turn over

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7 The diagram shows a section through an alveolus and through a capillary.

wall of alveolus
air

capillary red
wall blood cells

capillary

low carbon dioxide Y

concentration

high carbon dioxide

concentration

How does carbon dioxide move from Y to X?

A by diffusion
B by osmosis
C by translocation
D by transpiration

8 Which part of a plant root hair is partially permeable?

A the cell sap

B the cell surface membrane
C the cell vacuole
D the cell wall

© UCLES 2018 0610/23/M/J/18

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9 The table shows the results of food tests carried out on a fruit.

test Benedict’s biuret ethanol iodine

result positive positive negative negative

What did the fruit contain?

A fat and reducing sugar

B fat and starch
C protein and reducing sugar
D protein and starch

10 An experiment was carried out to investigate the effect of pH on enzyme action. The graph shows
the results.

y-axis

x-axis

What are the labels for the x-axis and the y-axis?

x-axis y-axis

A pH rate of reaction
B pH time
C rate of reaction pH
D time pH

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11 The diagram shows a section through a leaf.

S R

What are structures P, Q, R and S?

P Q R S

A chloroplast phloem palisade tissue xylem

B cuticle xylem chloroplast stoma
C phloem palisade tissue cuticle stoma
D xylem chloroplast phloem cuticle

12 A lack of which dietary component can result in constipation?

A fat
B fibre (roughage)
C carbohydrate
D protein

13 A woman requires more calcium in her diet when she is pregnant.

Which statement explains why?

A bone growth in the fetus

B muscle growth in the fetus
C production of haemoglobin in the fetus
D to provide energy for the fetus

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14 The diagram shows part of the alimentary canal.

M
K

Which row correctly identifies the structures labelled J to M?

J K L M

A oesophagus pancreas small intestine stomach

B pancreas small intestine stomach oesophagus
C small intestine stomach oesophagus pancreas
D stomach oesophagus pancreas small intestine

15 The diagram shows the pathway of water from the soil through a plant.

soil → X → Y → Z → mesophyll cells

Which cells are represented by X, Y and Z?

X Y Z

A root hair cells root cortex cells xylem

B root hair cells xylem root cortex cells
C xylem root cortex cells root hair cells
D xylem root hair cells root cortex cells

16 What will not affect the rate of transpiration?

A humidity of the atmosphere

B number of open stomata
C rate of respiration
D temperature

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17 A student places two samples of crushed apple into two beakers, P and Q. The samples are of
equal size. She adds 5 cm3 of pectinase solution to beaker P and 5 cm3 of water to beaker Q.

After five minutes, she places the samples of crushed apple into two different filter funnels, and
measures the volume of juice filtering through from each sample over a period of 10 minutes.

Which graph shows her results?

A B

Q P

total volume total volume

of juice filtered P of juice filtered
through through Q

0 0
0 time 0 time

C D

P
Q

total volume total volume

of juice filtered of juice filtered Q
through P through

0 0
0 time 0 time

18 During the process of blood clotting, damage to blood vessels stimulates L, and M is converted
to N.

What are L, M and N?

L M N

A fibrin platelets fibrinogen

B fibrinogen platelets fibrin
C platelets fibrin fibrinogen
D platelets fibrinogen fibrin

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19 A child is vaccinated against measles. After a period of time the child is infected with the measles
virus.

The graph shows the concentration of measles antibodies in the child’s bloodstream during this
time.

antibody
concentration
in the blood

time

Which statement is consistent with the information in the graph?

A After the vaccination, the child produced memory cells.

B The child had passive immunity against measles.
C The measles virus contains antibodies.
D The vaccination failed to protect the child against measles.

20 Muscles are responsible for the ventilation of the lungs during breathing.

Which row describes their action during the inspiration of air?

diaphragm external internal

muscles intercostal muscles intercostal muscles

A contract contract relax

B contract relax contract
C relax contract relax
D relax relax contract

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21 A student investigated aerobic respiration.

gauze drop of liquid

soda lime

woodlice capillary tube

Soda lime absorbs carbon dioxide.

If the woodlice are respiring aerobically, what will happen to the drop of liquid?

A It will move towards the woodlice as oxygen is used up and carbon dioxide is released.
B It will move away from the woodlice as oxygen is used up and carbon dioxide is released.
C It will not move as carbon dioxide is used up and oxygen is released.
D It will not move as oxygen is used up and carbon dioxide is released.

22 The diagram shows a kidney and associated structures.

blood in

blood out

What is the name of structure X?

A pulmonary artery
B pulmonary vein
C renal artery
D renal vein

23 What is the correct sequence in a reflex action?

A receptor → stimulus → motor neurone → relay neurone → sensory neurone → effector

B receptor → stimulus → sensory neurone → relay neurone → motor neurone → effector

C stimulus → receptor → motor neurone → relay neurone → sensory neurone → effector

D stimulus → receptor → sensory neurone → relay neurone → motor neurone → effector

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24 The diagram shows the cross-section of an eye.

Which statement is true when a person views a near object?

A E contracts; G is pulled less; F bulges less; more refraction of light takes place
B E contracts; G is pulled less; F bulges more; more refraction of light takes place
C E relaxes; G is pulled less; F bulges less; less refraction of light takes place
D E relaxes; G is pulled more; F bulges more; less refraction of light takes place

25 Compared to the hormonal system, the responses of the nervous system are

A faster and of longer-duration.

B faster and of shorter-duration.
C slower and of longer-duration.
D slower and of shorter-duration.

26 In an experiment to investigate phototropism, a plant shoot is grown with light coming from one
side only.

After two days, in which region has the greatest rate of growth occurred?

D
A
C
light B light

start of experiment after two days

© UCLES 2018 0610/23/M/J/18 [Turn over

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27 Crop plants produced by asexual reproduction are identical. This can be a disadvantage.

Which statements describe disadvantages?

1 Crop plants are produced rapidly.

2 A disease could kill all of the plants.
3 Only one parent is needed.
4 The plants cannot adapt to environmental changes.

A 1 and 2 B 1 and 3 C 2 and 4 D 3 and 4

28 The table shows some features of artificial insemination and in-vitro fertilisation.

Which row shows the features that are correct for both artificial insemination and in-vitro
fertilisation?

fertilisation happens implantation happens involves pregnancy

outside the female outside the female sexual develops naturally
reproductive system reproductive system intercourse after implantation

A
B
C
D

29 The graph shows the concentration of four hormones during the menstrual cycle.

Which line represents progesterone?

hormone B
level C
D

0 14 28
ovulation

day of cycle

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30 Cystic fibrosis is an inherited disease. The allele for cystic fibrosis is recessive.

A woman is heterozygous and her partner is homozygous dominant.

What is true of any children they produce?

A All of their children will have cystic fibrosis.

B There is a one in two chance of being heterozygous.
C There is a one in four chance of being heterozygous.
D There is no chance of having the cystic fibrosis allele.

31 Which graph shows the correct change in mass of DNA in one cell during cell division by mitosis?

A B

mass of DNA mass of DNA

0 0
0 time 0 time

C D

mass of DNA mass of DNA

0 0
0 time 0 time

32 Cell X contains 16 chromosomes. It divides by meiosis.

How many chromosomes do each of the new cells contain?

A 4 B 8 C 16 D 32

33 Which statement about blood groups in humans is correct?

A They are determined by genes and the environment.

B They are determined only by the environment.
C They are determined only by genes.
D They show continuous variation.

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34 Plants are adapted to survive in different environments.

Which are features of xerophytes?

number
cuticle
of stomata

A thick few
B thick many
C thin few
D thin many

35 In which form is nitrogen taken up by the roots of plants?

A as amino acids
B as nitrate ions
C as protein
D as urea

36 What is a community?

A a unit containing all the organisms in a given area, and their environment, interacting
together
B a unit in which energy is transferred from one organism to the next
C all of the populations of different species in an ecosystem
D all the organisms of one species in a given area

37 Which feature of bacteria makes it possible for them to be used to produce human insulin?

A Bacteria possess plasmids.

B Bacteria possess exactly the same DNA base sequences as humans.
C Bacteria possess the same genes for insulin.
D Bacteria possess the same number of chromosomes as humans.

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38 In some areas, farmers who grow genetically modified (GM) corn have to make sure there is a
gap between GM and non-GM crops.

What is the reason for leaving a gap between the crops?

A so they can get large machinery into the fields

B to prevent cross-pollination between GM and non-GM crops
C to prevent disease spreading between crops
D to prevent pests attacking crops

39 How does eutrophication lead to the death of aquatic organisms?

A algae not releasing enough oxygen

B algae respiring instead of photosynthesising
C decomposer bacteria lowering oxygen concentration in the water
D poisoning due to carbon dioxide accumulation in the water

40 What is an example of sustainable development?

A burning more fossil fuels to provide more energy

B catching more fish to feed a growing population
C clearing tropical forest to plant large areas of oil palm plants
D selective felling of forest trees for timber and replanting cleared areas

© UCLES 2018 0610/23/M/J/18

 Cambridge Assessment International Education
Cambridge International General Certificate of Secondary Education

BIOLOGY 0610/23
Paper 2 Multiple Choice (Extended) May/June 2019
45 minutes
Additional Materials: Multiple Choice Answer Sheet
Soft clean eraser
*2457016502*

Soft pencil (type B or HB is recommended)

READ THESE INSTRUCTIONS FIRST

Write in soft pencil.

Do not use staples, paper clips, glue or correction fluid.
Write your name, centre number and candidate number on the Answer Sheet in the spaces provided
unless this has been done for you.
DO NOT WRITE IN ANY BARCODES.

There are forty questions on this paper. Answer all questions. For each question there are four possible
answers A, B, C and D.
Choose the one you consider correct and record your choice in soft pencil on the separate Answer Sheet.

Read the instructions on the Answer Sheet very carefully.

Each correct answer will score one mark. A mark will not be deducted for a wrong answer.
Any rough working should be done in this booklet.
Electronic calculators may be used.

This syllabus is regulated for use in England, Wales and Northern Ireland as a Cambridge International Level 1/Level 2 Certificate.

This document consists of 18 printed pages and 2 blank pages.

IB19 06_0610_23/3RP
© UCLES 2019 [Turn over
 2

1 Students find a small organism in a pond. They catch it and put it into a large jar of water. They
see that the organism swims away from light. It lays some eggs before they put it back into the
pond.

Which characteristics of living things did the students see in this organism?

A excretion, growth and respiration

B growth, nutrition and sensitivity
C movement, reproduction and sensitivity
D movement, reproduction and respiration

2 The diagram shows how Homo sapiens (modern people) could have evolved from earlier
ancestors.

Homo sapiens (modern people)

Homo heidelbergensis

Homo erectus

Homo habilis

Which statement about modern people and their ancestors is correct?

A They are in the same species and the same genus.

B They are in the same species but not the same genus.
C They are in the same genus but not the same species.
D They are neither the same species nor the same genus.

3 In cells with a high respiration rate, what would be found in the cytoplasm in increased numbers?

A mitochondria
B ribosomes
C rough endoplasmic reticulum
D vesicles

© UCLES 2019 0610/23/M/J/19

 3

4 Which features are possessed by all plant cells?

a cell wall chloroplasts

A key
B = present
C = absent
D

5 The diagram shows a mitochondrion.

1 μm

The diagram is 70 mm long.

What is the magnification of the diagram?

A ×0.0007 B ×70 C ×7000 D ×70 000

6 The diagram shows a test-tube containing clear jelly. A drop of blue ink is injected into the middle
of the jelly.

clear jelly
drop of blue ink

The blue colour of the ink spreads throughout the jelly.

By which process does the blue ink spread through the jelly?

A active transport
B catalysis
C diffusion
D osmosis

© UCLES 2019 0610/23/M/J/19 [Turn over

 4

7 Which row describes active transport?

movement of uses energy through a cell

water from respiration membrane

A yes no no
B yes no yes
C no yes no
D no yes yes

8 Which reagent is used when testing a food for vitamin C?

A Benedict’s solution
B DCPIP
C ethanol
D iodine solution

9 Small molecules are used as the basic units in the synthesis of large food molecules.

Which statement is correct?

A Amino acids are basic units of carbohydrates.

B Fatty acids are basic units of glycogen.
C Glycerol is a basic unit of oils.
D Simple sugar is a basic unit of protein.

© UCLES 2019 0610/23/M/J/19

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10 The diagrams show a protease enzyme catalysing the breaking of part of a protein molecule into
smaller pieces.

Which diagram has three correct labels?

A B
product
active site
substrate product

enzyme enzyme

C D

active site active site

substrate

enzyme substrate

product

11 The diagram shows an experiment to investigate the balance between respiration and
photosynthesis.

In which tube are photosynthesis and respiration taking place at the same time?

A B C D

black
water polythene
to keep
snail out light
light light light
pond
weed

© UCLES 2019 0610/23/M/J/19 [Turn over

 6

12 The diagrams show the structure of four different cells from a plant.

Which cell is from the upper epidermis of a leaf?

A B

C D

© UCLES 2019 0610/23/M/J/19

 7

13 The diagram shows the human alimentary canal.

2 3
4

Which pair of structures both produce digestive enzymes?

A 1 and 2 B 1 and 3 C 2 and 4 D 3 and 5

14 The cholera bacterium produces toxins that cause chloride ions to be secreted into the small
intestine.

How does this affect the water potential of blood in the intestinal capillaries and the intestinal
contents?

water potential
blood in contents of
capillaries small intestine

A lowered lowered
B lowered raised
C raised lowered
D raised raised

© UCLES 2019 0610/23/M/J/19 [Turn over

 8

15 Starch in food is digested in two stages.

In which parts of the alimentary canal do the two stages occur?

starch into maltose maltose into glucose

A duodenum stomach
B lining of small intestine mouth
C mouth lining of small intestine
D stomach duodenum

16 A celery stalk was placed into a beaker of blue dye. When the dye reached the leaves, the stalk
was taken out and a section was cut, as shown in the diagram.

celery stalk

cut

blue dye

Which diagram shows the appearance of the cut end of the stalk?

A B C D

blue dye blue dye blue dye

© UCLES 2019 0610/23/M/J/19

 9

17 The table shows the rate of water flow through a tree over a 12 hour period.

rate of flow
time of day
/ cm per hour

17:00 100
19:00 120
11:00 140
13:00 250
15:00 300
17:00 260
19:00 180

What conclusion can be drawn from the table?

A Between 7:00 and 17:00 hours the rate of flow continuously increases.
B The greatest increase in rate of flow in a two-hour period is between 11:00 and 13:00 hours.
C Water does not flow up through a tree at night.
D Water flow is affected by humidity.

© UCLES 2019 0610/23/M/J/19 [Turn over

 10

18 Scientists investigate the movement of substances in a plant.

They cut a ring of tissue from the stem.

Removing the tissue removes some of the transport vessels found around the edge of the stem.

A few days later they notice swelling above the area where the tissue has been removed.

leaves

tissue
removed time swelling

roots

What causes the swelling?

A Phloem vessels have been removed and sucrose cannot move to the sink.
B Phloem vessels have been removed and sucrose cannot move to the source.
C Xylem vessels have been removed and minerals cannot move to the sink.
D Xylem vessels have been removed and minerals cannot move to the source.

© UCLES 2019 0610/23/M/J/19

 11

19 The diagram shows cross-sections through three types of blood vessel, not drawn to the same
scale.

V W X

Which section is from a vein and which is from a capillary?

vein capillary

A V W
B W V
C W X
D X W

20 By which route would an HIV infection not be transmissible?

A blood
B saliva
C sharing needles for injections
D semen

21 The diagram illustrates changes in air pressure taking place inside the lungs during a complete
cycle of breathing. Atmospheric pressure is 101 kPa.

At which point on the diagram are the ribs beginning to be lowered?

B
102

pressure
in lungs 101
/ kPa

D
100
time

© UCLES 2019 0610/23/M/J/19 [Turn over

 12

22 Which process uses energy released by respiration?

A diffusion
B evaporation
C growth
D osmosis

23 The volume of oxygen taken up by germinating seeds was measured.

The graph shows the results.

2.0

1.8

1.6

1.4

1.2
volume of oxygen
taken up / cm3 1.0

0.8

0.6

0.4

0.2

0
0 5 10 15 20
time / minutes

What is the rate of oxygen uptake?

A 0.08 cm3 per minute

B 8.00 cm3 per minute
C 10.8 cm3 per minute
D 12.50 cm3 per minute

© UCLES 2019 0610/23/M/J/19

 13

24 The diagrams show the structures on each side of a synaptic cleft.

Which diagram is correctly labelled?

A B
synaptic direction synaptic direction
cleft of impulse cleft of impulse

released released
neurotransmitter neurotransmitter
neurotransmitter neurotransmitter
receptor receptor
molecules molecules

C D
synaptic direction synaptic direction
cleft of impulse cleft of impulse

released released
neurotransmitter neurotransmitter
neurotransmitter neurotransmitter
receptor receptor
molecules molecules

25 Dialysis is a method of regulating the composition of blood when the kidneys are not working
properly.

Which substance is absent from fresh dialysis fluid?

A bile
B glucose
C salt
D water

© UCLES 2019 0610/23/M/J/19 [Turn over

 14

26 The diagram shows a vertical section through part of a human eye. A fly is coming nearer to the
eye. The eye begins to focus the image of the fly on its retina.

fly
R

How do the labelled parts of the diagram change?

Q R S

A contracts thinner tighter

B relaxes fatter slacker
C contracts fatter slacker
D relaxes thinner tighter

27 Where is glucagon secreted, and what is its effect on blood glucose concentration?

effect on blood
secreted by
glucose concentration

A liver increases
B liver decreases
C pancreas increases
D pancreas decreases

28 Which statement about antibiotics is correct?

A Antibiotics are effective against viral diseases.

B Antibiotics are produced by white blood cells.
C Antibiotics can provide pain relief.
D Antibiotics can stop bacteria making new cell walls.

© UCLES 2019 0610/23/M/J/19

 15

29 Where is progesterone produced?

A ovary
B pituitary gland
C prostate gland
D uterus

30 Which feature allows the sperm to dissolve the jelly coating of the egg cell?

A acrosome
B flagellum
C mitochondria
D nucleus

31 Parents with alleles IAIB and IoIo can produce children with which blood groups?

A A and B
B AB
C A and O
D B and O

32 The diagram shows the chromosomes in the nucleus of a cell that divides by mitosis.

Which diagram shows the chromosomes in the nucleus of one of the daughter cells produced?

A B C D

© UCLES 2019 0610/23/M/J/19 [Turn over

 16

33 During protein synthesis, what is the function of the ribosome?

A assemble amino acids in a chain

B carry a copy of a gene to the cytoplasm
C contain the code for the synthesis of a protein
D determine the order of bases in the protein

34 The table shows some inherited features.

Which features show co-dominance?

blood colour
sex
group blindness

A key
B = co-dominant
C = not co-dominant
D

35 These events may happen when an antibiotic is used to treat a bacterial infection.

1 The antibiotic kills most of the bacteria.

2 The antibiotic resistant bacteria reproduce.
3 The antibiotic resistant bacteria survive.
4 Some bacteria mutate and are resistant to the antibiotic.

Which sequence may produce a strain of antibiotic resistant bacteria?

A 1→2→3→4

B 2→3→1→4

C 3→1→4→2

D 4→1→3→2

© UCLES 2019 0610/23/M/J/19

 17

36 The diagram shows the energy within the producers in an ecosystem and how much is
transferred to primary consumers and eventually lost to the environment.

45 000 kJ 4500 kJ
Sun

primary
producers secondary
consumers
50 000 kJ consumers
5000 kJ

How much energy is transferred from primary consumers to secondary consumers?

A 5 kJ B 50 kJ C 500 kJ D 5000 kJ

37 Which is the tertiary consumer in this food chain?

A B C D
aquatic plant → pond snails → small fish → large fish → fish eagles

38 Scientists in one country are using bacteria to break down crude oil in abandoned oil fields. This
produces natural gas which is used as a fuel.

Why are bacteria useful in this example of biotechnology?

A Bacteria are involved in the nitrogen cycle.

B Bacteria are microorganisms.
C Bacteria can be pathogens.
D Bacteria can reproduce very quickly.

© UCLES 2019 0610/23/M/J/19 [Turn over

 18

39 The diagrams show the stages in the production of human insulin.

Which stage uses the enzyme DNA ligase?

A B

gene for insulin identified and plasmid is removed from

removed from a human cell a bacterium and cut open

C D

the gene for insulin is the plasmid is inserted into a bacterium

inserted into the plasmid which reproduces and insulin is produced

40 What is an undesirable effect of deforestation?

A habitat creation
B loss of soil
C more species
D reduced carbon dioxide in the atmosphere

© UCLES 2019 0610/23/M/J/19

 Cambridge IGCSE™

BIOLOGY 0610/23
Paper 2 Multiple Choice (Extended) May/June 2020
45 minutes

You must answer on the multiple choice answer sheet.

*9413881825*

You will need: Multiple choice answer sheet

Soft clean eraser
Soft pencil (type B or HB is recommended)

INSTRUCTIONS
• There are forty questions on this paper. Answer all questions.
• For each question there are four possible answers A, B, C and D. Choose the one you consider correct
and record your choice in soft pencil on the multiple choice answer sheet.
• Follow the instructions on the multiple choice answer sheet.
• Write in soft pencil.
• Write your name, centre number and candidate number on the multiple choice answer sheet in the
spaces provided unless this has been done for you.
• Do not use correction fluid.
• Do not write on any bar codes.
• You may use a calculator.

INFORMATION
• The total mark for this paper is 40.
• Each correct answer will score one mark. A mark will not be deducted for a wrong answer.
• Any rough working should be done on this question paper.

This document has 16 pages. Blank pages are indicated.

IB20 06_0610_23/4RP
© UCLES 2020 [Turn over
 2

1 The diagram shows what happened in an experiment with plant seedlings.

start next day

light light

Which characteristic of living things made the seedlings grow towards the light?

A excretion
B nutrition
C respiration
D sensitivity

2 A rat has the scientific name Rattus rattus.

What do the two parts of this name refer to?

A genus and species

B kingdom and genus
C kingdom and species
D variety and genus

3 Onion plant cells swell but do not burst when placed in distilled water.

Which cell component prevents the onion plant cells from bursting?

A cell membrane
B cell wall
C nucleus
D vacuole

© UCLES 2020 0610/23/M/J/20

 3

4 The diagram shows an onion plant epidermal cell.

The distance between X and Y on the diagram is 60 mm.

The actual length of the cell between X and Y was 150 µm.

X Y

What is the magnification of the cell?

A ×40 B ×250 C ×400 D ×2500

5 Which diagram shows the appearance of a plant cell several minutes after it has been placed in a
concentrated solution of sugar?

A B

C D

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 4

6 The diagram shows two adjacent plant cells.

cell X cell Y

high low
water water
potential potential

Which statement describes what will happen to the water in the cells?

A equal movement between cells

B net movement from X to Y
C net movement from Y to X
D no movement between cells

7 The diagram shows a section of DNA, with four bases identified on one strand.

Which sequence of bases would be on the other strand, starting from the top?

A AGTC B CTGA C GACT D TCAG

8 Which food-testing solution shows a positive result when it turns from blue to purple?

A Benedict’s solution
B biuret solution
C ethanol
D iodine solution

© UCLES 2020 0610/23/M/J/20

 5

9 Which statement about enzyme-controlled reactions is correct?

A During the reaction, a substrate changes into a product.

B The enzyme is slowly broken down during the reaction.
C The higher the pH the faster the reaction.
D The product is gradually used up during the reaction.

10 Increasing temperature above the optimum for the enzyme results in loss of enzyme activity.

How is this explained?

A less frequent collisions between the enzyme and the substrate

B reduced kinetic energy of the enzyme molecule
C substrate molecules move faster and effective collisions are less likely
D the shape of the active site is changed and the substrate will no longer fit into it

11 The diagram shows how the rate of photosynthesis varies with light intensity.

The four curves show different conditions of temperature and carbon dioxide concentration.

30 °C, 0.2% CO2

20 °C, 0.2% CO2

rate of
photosynthesis 30 °C, 0.1% CO2
P
20 °C, 0.1% CO2

light intensity

What limits the rate of photosynthesis at point P?

carbon dioxide
light intensity temperature
concentration

A key
B = yes
C = no
D

© UCLES 2020 0610/23/M/J/20 [Turn over

 6

12 Why do plants need nitrate ions?

A to make amino acids

B to make fats
C to make glucose
D to make starch

13 The table shows the percentage of the daily recommended intake of nutrients in a serving of four
foods.

Which food would be the best choice to prevent scurvy?

percentage of daily recommended intake

in a serving of food
vitamin vitamin
calcium iron
C D

A 71 1 0 6
B 24 11 2 73
C 3 3 72 0
D 1 72 1 0

14 The diagram shows a villus in the small intestine.

What is absorbed at X?

A fats
B glucose
C glycogen
D starch

© UCLES 2020 0610/23/M/J/20

 7

15 Samphire is a plant that grows in coastal areas. It has adaptations that enable it to live in areas
with high salt concentration in the soil and strong winds.

Which adaptations would samphire possess to minimise water loss from root cells by osmosis
and leaves by evaporation?

salt concentration
leaf surface area
in root cells

A high high
B high low
C low high
D low low

16 Which row correctly states the pair of conditions that will result in the highest rate of
transpiration?

temperature humidity

A high low
B high high
C low high
D low low

17 The diagram shows some veins in the human arm and the valves that they contain.

If blood is squeezed out of section X–Y, where should pressure be placed on a vein to stop blood
flowing into this section again?

B
valve

X Y C

© UCLES 2020 0610/23/M/J/20 [Turn over

 8

18 The diagram shows some of the blood vessels leaving and returning to the heart.

lungs

heart

body

Which row is correct for blood vessels X and Y?

description of description of
name of blood name of blood
oxygen content oxygen content
vessel X vessel Y
of the blood in X of the blood in Y

A aorta deoxygenated pulmonary artery oxygenated

B aorta oxygenated pulmonary vein deoxygenated
C vena cava deoxygenated pulmonary vein oxygenated
D vena cava oxygenated pulmonary artery deoxygenated

19 Vaccinations can be given to gain active immunity.

Which statement about this type of vaccination is correct?

A The vaccination contains antibodies.

B The vaccination must contain harmful pathogens.
C The vaccination triggers antibody production in the body.
D The vaccination triggers antigen production in the body.

© UCLES 2020 0610/23/M/J/20

 9

20 The diagram shows an alveolus and capillary in a human lung.

alveolus

capillary

Which row shows the correct gas and concentrations for diffusion from X to Y in normal
conditions?

at point X at point Y

A high concentration of carbon dioxide low concentration of carbon dioxide

B high concentration of oxygen low concentration of oxygen
C low concentration of carbon dioxide high concentration of carbon dioxide
D low concentration of oxygen high concentration of oxygen

21 The symbol equation for aerobic respiration is shown.

C6HxOy + 6O2 → 6COz + 6H2O

Which numbers represent the letters shown in the equation as x, y and z?

x y z

A 2 12 6
B 6 2 12
C 6 12 2
D 12 6 2

© UCLES 2020 0610/23/M/J/20 [Turn over

 10

22 Blood glucose level is kept between 5–7 mmol per dm3. The concentration of glucose in the
intestine varies and is often less than that value.

What would be required for the absorption of glucose into the blood when the concentration of
glucose in the intestine is less than 5 mmol per dm3?

1 mitochondria
2 oxygen
3 membrane proteins

A 1 only B 1 and 2 only C 2 and 3 only D 1, 2 and 3

23 The diagram shows a synapse between a motor neurone and a relay neurone.

relay neurone
P

Q
motor neurone

What passes from P to Q?

A an electrical impulse
B an enzyme
C a hormone
D a neurotransmitter

24 What change occurs in a ‘fight or flight’ situation?

A constriction of pupils
B decrease in breathing rate
C decrease in pulse rate
D increase in blood glucose concentration

25 What happens when a person enters a very hot room?

A Sweating decreases and vasoconstriction increases.

B Sweating decreases and vasodilation decreases.
C Sweating increases and vasoconstriction increases.
D Sweating increases and vasodilation increases.

© UCLES 2020 0610/23/M/J/20

 11

26 Which disease is caused by a virus?

A AIDS
B kwashiorkor
C cholera
D MRSA infection

27 Which row describes cross-pollination?

pollen transferred from anther to stigma of

a flower on a a flower on a
a different flower
different plant of different plant of a
on same plant
same species different species

A
B
C
D

28 The diagram shows the head of a sperm.

What are the functions of structures X and Y?

X Y

A protein synthesis digestion of egg cell jelly coat

B releases energy for movement digestion of egg cell jelly coat
C protein synthesis energy store
D releases energy for movement energy store

© UCLES 2020 0610/23/M/J/20 [Turn over

 12

29 Which row describes what happens in the production of proteins?

what forms the genetic what carries a copy of the

what the DNA codes for
code gene to the cytoplasm

A sequence of amino acids sequence of bases mRNA

B sequence of amino acids sequence of proteins ribosomes
C sequence of bases sequence of amino acids mRNA
D sequence of bases sequence of proteins ribosomes

30 Which statement about meiosis is correct?

A Meiosis produces diploid cells.

B Meiosis produces genetically identical cells.
C Meiosis produces gametes.
D Meiosis produces cells for growth of tissues.

31 The diagram shows the inheritance of ABO blood groups. The blood groups of some of the
individuals are given.

A
1 2

B O
3 4 5

O A
6 7

What could be person 2’s genotype?

A IAIo B IBIB C IBIo D IoIo

32 In mice, the allele for black hair is dominant to the allele for brown hair.

What proportion of offspring will have brown hair if a cross is made between a homozygous black
mouse and a heterozygous black mouse?

A 0% B 25% C 50% D 100%

© UCLES 2020 0610/23/M/J/20

 13

33 The graph shows the masses of two different types of tomato.

type 1 type 2

number of
tomatoes

0 20 40 60 80 100 120 140 160 180 200 220 240

mass / g

What can be concluded from the graph?

A Genes do not affect the mass of tomatoes.

B Type 1 tomatoes show continuous variation.
C Type 2 tomatoes are sometimes smaller than type 1 tomatoes.
D Type 2 tomatoes show discontinuous variation.

34 Which adaptation may be present in a xerophyte?

A leaves with small surface area and large numbers of stomata

B little or no xylem tissue and leaves with large surface area
C stomatal hairs and rolled leaves
D thin or no cuticle and deep roots

35 The diagram shows a food chain in a rock pool.

seaweed → whelks → crabs → seagulls

What will happen if the number of secondary consumers increases?

There will be

A fewer crabs.
B fewer seagulls.
C fewer whelks.
D less seaweed.

© UCLES 2020 0610/23/M/J/20 [Turn over

 14

36 What is defined as ‘all of the populations of different species in an ecosystem’?

A community
B environment
C habitat
D trophic level

37 What is the role of anaerobic respiration in bread-making?

A to produce alcohol to flavour the bread

B to produce gas to make the bread rise
C to release enough energy to bake the bread
D to release enough lactic acid to kill the yeast

38 A crop plant has been genetically modified to make it resistant to herbicides.

Which is a possible disadvantage of introducing this new crop plant?

A Loss of weeds reduces competition.

B Some weeds might become resistant to the herbicide.
C The crop plant is unharmed and produces a higher yield.
D The new gene will appear in new generations of the crop.

39 Chickens are birds that are farmed to produce eggs for human consumption.

A type of chicken has been bred to lay more eggs.

Which method would be used to produce this type of chicken?

A asexual reproduction
B biotechnology
C natural selection
D selective breeding

40 When a river is polluted by fertiliser, the following processes may occur.

1 increased aerobic respiration of decomposers

2 increased growth of producers
3 decreased oxygen concentration in the water

What is the correct sequence for these processes?

A 1→2→3 B 1→3→2 C 2→1→3 D 2→3→1

© UCLES 2020 0610/23/M/J/20

 Cambridge IGCSE™

BIOLOGY 0610/23
Paper 2 Multiple Choice (Extended) May/June 2021
45 minutes

You must answer on the multiple choice answer sheet.

*0328570865*

You will need: Multiple choice answer sheet

Soft clean eraser
Soft pencil (type B or HB is recommended)

INSTRUCTIONS
 There are forty questions on this paper. Answer all questions.
 For each question there are four possible answers A, B, C and D. Choose the one you consider correct
and record your choice in soft pencil on the multiple choice answer sheet.
 Follow the instructions on the multiple choice answer sheet.
 Write in soft pencil.
 Write your name, centre number and candidate number on the multiple choice answer sheet in the
spaces provided unless this has been done for you.
 Do not use correction fluid.
 Do not write on any bar codes.
 You may use a calculator.

INFORMATION
 The total mark for this paper is 40.
 Each correct answer will score one mark.
 Any rough working should be done on this question paper.

This document has 16 pages. Any blank pages are indicated.

IB21 06_0610_23/3RP
© UCLES 2021 [Turn over
 2

1 What is a characteristic of all living organisms?

A breathing
B circulation
C egestion
D sensitivity

2 What is the most accurate method of classifying animals?

A comparing bones
B comparing the morphology of organisms
C identifying similarities in anatomy
D identifying similarities in DNA base sequences

3 Scientists discover a new species of animal.

It has a segmented body with two pairs of legs on each segment.

To which group of animals does this new species belong?

A arachnids
B crustaceans
C insects
D myriapods

4 In which part of a cell does photosynthesis take place?

A vacuole
B nucleus
C chloroplast
D cytoplasm

© UCLES 2021 0610/23/M/J/21

 3

5 The diagram shows some of the blood vessels and other structures in the human body.

The blood vessels shown are all parts of the same

A cell.
B organ.
C organ system.
D tissue.

6 A photograph shows a plant cell nucleus measuring 2 mm across.

If the magnification of the cell is 500, what is the actual size of the nucleus?

A 0.00002 mm B 0.004 mm C 0.04 mm D 250 mm

7 By which process do oxygen and carbon dioxide move between cells and capillaries?

A breathing
B diffusion
C excretion
D respiration

© UCLES 2021 0610/23/M/J/21 [Turn over

 4

8 Which process is involved in the uptake of glucose by the epithelial cells of kidney tubules?

A active transport
B osmosis
C translocation
D transpiration

9 Which element is found in proteins but not carbohydrates?

A carbon
B hydrogen
C nitrogen
D oxygen

10 A DNA sample was tested to identify its bases.

35% of the bases in the DNA were G.

Which row shows the percentages of the other bases?

percentage of bases
A C T

A 15 15 35
B 15 35 15
C 35 15 35
D 35 35 15

11 Starch is digested by amylase in the mouth, but it is not digested in the stomach.

What is the reason for this?

A All starch digestion is completed in the mouth.

B The pH in the stomach is not suitable for the amylase to work.
C The starch does not stay in the stomach long enough to be digested.
D The temperature in the stomach is not suitable for the amylase to work.

© UCLES 2021 0610/23/M/J/21

 5

12 Which type of molecule are enzymes made of?

A carbohydrate
B fat
C protein
D vitamin

13 A plant with striped leaves was kept in bright light for six hours.

white stripe

green stripe

A leaf was taken from the plant and the chlorophyll was removed. The leaf was then tested for
starch using iodine solution.

Which diagram shows the result of the test?

A B C D
yellow-brown white blue-black yellow-brown

blue-black blue-black green green

© UCLES 2021 0610/23/M/J/21 [Turn over

 6

14 The graph shows daily carbon dioxide uptake and transpiration by the plant Agave americana.

The plant is adapted to live in very dry conditions.

10 0.6
CO2 uptake
8
0.4 transpiration
CO2 uptake 6
/ g H2O
/ mg per dm2
transpiration per dm2
per hour 4
0.2 per hour
2

0 0
0 4 8 12 16 20 24
time of day / hours

What can be concluded from this graph?

A More stomata are closed during dark periods.

B More stomata are closed during light periods.
C There is no carbon dioxide uptake during dark periods.
D There is no water uptake during light periods.

15 Statements 1 to 4 describe stages in the development of cholera.

1 Chloride ions are secreted into the gut.

2 Osmosis causes water to move into the gut.
3 The infected person becomes dehydrated.
4 Toxins are produced by the pathogenic bacteria.

What is the correct sequence of the four stages?

A 1234

B 1432

C 4123

D 4132

16 What is the cause of the start of dental decay?

A Acid dissolves dentine.

B Acid dissolves enamel.
C Sugars dissolve dentine.
D Sugars dissolve enamel.

© UCLES 2021 0610/23/M/J/21

 7

17 The diagram shows one of the stomata of a leaf, and some of the cells that are near it.

X
mesophyll cell

guard Y
cell

During transpiration, what describes the movement of water at X and at Y?

movement of movement of
water at X water at Y

A evaporation diffusion
B evaporation osmosis
C osmosis diffusion
D osmosis osmosis

© UCLES 2021 0610/23/M/J/21 [Turn over

 8

18 A ring of phloem tissue was removed from the stem of a plant, as shown in the first diagram.
Carbon dioxide containing radioactive carbon was supplied to the leaf of the plant. The second
diagram shows where radioactive carbon was present after three hours.

clear bag

shaded and black

area with carbon dioxide areas show where
phloem containing radioactive carbon
removed radioactive carbon is present

start after three hours

Which statements does the experiment support?

1 Translocation of sugar only occurs in one direction.

2 Translocation occurs in the phloem.
3 Translocation requires energy.

A 1 only B 1 and 2 C 2 only D 2 and 3

19 Through which blood vessels does blood flow into the heart?

1 pulmonary artery
2 pulmonary vein
3 vena cava
4 aorta

A 1 and 2 B 1 and 4 C 2 and 3 D 2 and 4

20 What is an angioplasty?

A a recording of the heart’s electrical activity to check for abnormalities

B an operation to insert a new vessel that diverts blood around a narrowed section
C the insertion of a tube into a blood vessel to allow blood to flow more freely
D the widening of a blood vessel by means of a balloon-like device

© UCLES 2021 0610/23/M/J/21

 9

21 A child is vaccinated against measles. After a period of time the child is infected with the measles
virus.

The graph shows the concentration of measles antibodies in the child’s bloodstream during this
time.

antibody
concentration
in the blood

time

Which statement is consistent with the information in the graph?

A After the vaccination, the child produced memory cells.

B The child had passive immunity against measles.
C The measles virus contains antibodies.
D The vaccination failed to protect the child against measles.

22 Which sequence of changes takes place when we breathe in?

A diaphragm contracts  volume of thorax increases  pressure in lungs decreases

B diaphragm contracts  volume of thorax increases  pressure in lungs increases

C diaphragm relaxes  volume of thorax increases  pressure in lungs decreases

D diaphragm relaxes  volume of thorax increases  pressure in lungs increases

23 Which statement applies to respiration?

A It involves enzymes.
B Energy is absorbed.
C It only takes place in animal cells.
D Oxygen is released.

© UCLES 2021 0610/23/M/J/21 [Turn over

 10

24 Which statement about respiration is correct?

A Deep breathing after exercise reduces an oxygen debt.

B Lactic acid produced by aerobic respiration causes an oxygen debt.
C The energy in ethanol molecules is released by muscle cells.
D The energy in lactic acid is released by anaerobic respiration.

25 A student carried out an experiment to investigate the effect of temperature on the volume of
urine produced.

Which row shows the experiment where the environmental temperature was increased from 20 C
to 40 C but no other changes were made?

urine produced
/ cm3 per hour
before after

A 60 60
B 80 40
C 120 145
D 100 130

26 Which row shows the levels of organisation for structures associated with the eye?

cell tissue organ organ system

A cone fovea endocrine eye

B rod retina eye nervous
C antibody muscle artery circulatory
D lymphocyte capillary vein sensory

27 Which row correctly compares hormonal control with nervous control?

speed of action how long the effects

of hormonal control of the hormone lasts

A rapid short
B slow long
C rapid long
D slow short

© UCLES 2021 0610/23/M/J/21

 11

28 Which statement about the regulation of human body temperature is correct?

A Vasoconstriction of skin arterioles occurs when the body temperature is too low.
B Vasodilation of skin arterioles occurs when the body temperature is too low.
C Vasoconstriction of skin capillaries occurs when the body temperature is too high.
D Vasodilation of skin capillaries occurs when the body temperature is too low.

29 Why are people advised not to drive a car after drinking an excessive quantity of alcohol?

A Alcohol is a depressant.
B Alcohol is a stimulant.
C Alcohol decreases reaction time.
D Alcohol is addictive.

30 What is a disadvantage of asexual reproduction when a new crop disease appears on a farm?

A Asexual reproduction only requires one parent plant.

B Asexual reproduction does not require a pollinator.
C Asexual reproduction does not lead to genetic variation in offspring.
D Asexual reproduction does not disperse offspring over a wide area.

31 Where is progesterone produced in the late stages of pregnancy?

A ovaries
B pancreas
C placenta
D uterus

© UCLES 2021 0610/23/M/J/21 [Turn over

 12

32 The diagram shows structures involved in the synthesis of an enzyme in a cell.

What is structure 2?

A amino acids
B DNA
C mRNA
D protein

33 Which definition of mitosis is correct?

A nuclear division giving rise to genetically different cells

B nuclear division giving rise to genetically identical cells
C fusion of nuclei giving rise to a genetically different cell
D fusion of nuclei giving rise to a genetically identical cell

34 What happens during meiosis?

A A haploid cell produces haploid cells that are genetically identical.

B A haploid cell produces haploid cells that are genetically different.
C A diploid cell produces haploid cells that are genetically identical.
D A diploid cell produces haploid cells that are genetically different.

© UCLES 2021 0610/23/M/J/21

 13

35 What is a correct description of a gene mutation?

A a duplicate copy of DNA

B a change in the base sequence of DNA
C an increase in the number of chromosomes
D a phenotypic variation

36 Adaptive features are inherited features that increase fitness.

What is the definition of fitness?

A artificial selection to improve organisms

B the change in adaptive features of a population over time
C the probability of an organism surviving and reproducing in the environment in which it is
found
D the probability of variation in a population

37 The diagram shows energy transfer through a food chain. The labelled arrows represent the
energy transfers.

air

X
W Y Z
Sun plant grasshopper frog

Which energy transfers are shown by the labelled arrows?

A X is heat energy transfer and Z is chemical energy transfer.

B Y is chemical energy transfer and X is light energy transfer.
C X is chemical energy transfer and Y is heat energy transfer.
D Z is heat energy transfer and W is light energy transfer.

© UCLES 2021 0610/23/M/J/21 [Turn over

 14

38 The organisms in a food chain can be represented by pyramids of numbers or pyramids of

biomass.

Which diagram represents a pyramid of numbers?

A B

blackbird fleas

ladybird rabbit

greenfly grass

rose bush

C D

starling sparrow hawk

lacewing blue tit

aphid caterpillar

elder tree oak tree

39 Scientists wanted to know which one of four different varieties of bacteria, A, B, C or D, would be
the best to use to make a protein.

They grew the bacteria for five days using the same starting mass of each bacterium. They then
measured the mass of bacteria and the mass of protein produced per gram of bacteria.

The results are shown in the table.

Which variety of bacteria should the scientists choose?

mass of protein
mass of bacteria mass of bacteria
/ mg protein per g of
at the start / g after five days / g
bacteria

A 2 200 10
B 2 800 1
C 2 100 12
D 2 100 6

© UCLES 2021 0610/23/M/J/21

 15

40 The graph shows the annual deforestation and annual net release of carbon dioxide from an area
of tropical forest between 1990 and 2001.

3.0 1400

2.5 1200
1000
annual 2.0
annual net
deforestation 800
1.5 release of
/ million
hectares 600 carbon dioxide
1.0 / million tonnes
400
0.5 200
0.0 0
1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001

year

key
annual deforestation
annual net release of carbon dioxide

Which statements are correct?

1 The highest rate of deforestation occurred in 1995.

2 There is a close relationship between annual deforestation and carbon dioxide
release.
3 The annual net release of carbon dioxide increases every year.

A 1 and 2 only B 1 and 3 only C 1, 2 and 3 D 2 and 3 only

© UCLES 2021 0610/23/M/J/21

 Cambridge IGCSE™

BIOLOGY 0610/23
Paper 2 Multiple Choice (Extended) May/June 2022
45 minutes

You must answer on the multiple choice answer sheet.

*4514030708*

You will need: Multiple choice answer sheet

Soft clean eraser
Soft pencil (type B or HB is recommended)

INSTRUCTIONS
 There are forty questions on this paper. Answer all questions.
 For each question there are four possible answers A, B, C and D. Choose the one you consider correct
and record your choice in soft pencil on the multiple choice answer sheet.
 Follow the instructions on the multiple choice answer sheet.
 Write in soft pencil.
 Write your name, centre number and candidate number on the multiple choice answer sheet in the
spaces provided unless this has been done for you.
 Do not use correction fluid.
 Do not write on any bar codes.
 You may use a calculator.

INFORMATION
 The total mark for this paper is 40.
 Each correct answer will score one mark.
 Any rough working should be done on this question paper.

This document has 12 pages.

IB22 06_0610_23/5RP
© UCLES 2022 [Turn over
 2

1 All living organisms release energy from nutrient molecules within their cells.

What is the name of this characteristic?

A growth
B nutrition
C respiration
D sensitivity

2 Which diagram shows a flower from a monocotyledon?

A B C D

3 The diagram shows a cross-section through two guard cells of a leaf.

W X

Which labelled structures would also be found in an animal cell?

A W and X B X and Y C Y and Z D Z and W

4 Which level of organisation is shown by the heart of a mammal?

A a cell
B a tissue
C an organ
D an organ system

© UCLES 2022 0610/23/M/J/22

 3

5 Female moths release chemicals into the air. Male moths detect these chemicals and fly towards
the females.

How do the chemicals spread through the air?

A active transport
B diffusion
C osmosis
D transpiration

6 The diagram shows a section through a mesophyll cell of a leaf.

Which part is partially permeable?

B
C
D

7 What are the smaller basic units of starch and glycogen molecules?

starch glycogen

A amino acids fatty acids and glycerol

B amino acids glucose
C glucose fatty acids and glycerol
D glucose glucose

8 DNA is made up of ......1...... strands coiled together. The strands contain chemicals called
......2...... . These chemicals form ......3...... , A pairing with T and C pairing with G.

Which words correctly complete gaps 1, 2 and 3?

1 2 3

A three amino acids cross-links

B two bases cross-links
C three bases proteins
D two amino acids proteins

© UCLES 2022 0610/23/M/J/22 [Turn over

 4

9 What is the correct definition of an enzyme?

A a carbohydrate that functions as a biological catalyst

B a protein that functions as a biological catalyst
C a substance that is changed by the reaction
D a substance made of fats that changes the rate of a reaction

10 Which statement describes the effect of temperature on enzymes?

A High temperatures denature enzymes making it difficult for substrate molecules to fit into the
active site.
B High temperatures denature enzymes making it easy for substrate molecules to fit into the
active site.
C Low temperatures denature enzymes making it difficult for substrate molecules to fit into the
active site.
D Low temperatures denature enzymes making it easy for substrate molecules to fit into the
active site.

11 The graph shows the rate of photosynthesis at different carbon dioxide concentrations.

rate of
photosynthesis

carbon dioxide
concentration

What could be the limiting factor of photosynthesis at X on the graph?

A oxygen
B carbon dioxide
C glucose
D light intensity

© UCLES 2022 0610/23/M/J/22

 5

12 The list shows features of a plant leaf.

1 air spaces between spongy mesophyll cells

2 chloroplasts in mesophyll cells
3 contains a natural insecticide
4 xylem vessels close to mesophyll cells

Which features are adaptations for photosynthesis?

A 1, 2 and 3 B 1, 2 and 4 C 1, 3 and 4 D 2, 3 and 4

13 Which nutrient is required to prevent scurvy?

A calcium
B iron
C vitamin C
D vitamin D

14 Which diagram represents the action of lipase?

A + +

key

B + + + enzyme

substance 1

C + + substance 2

substance 3

D + +

© UCLES 2022 0610/23/M/J/22 [Turn over

 6

15 The image shows a cross-section of part of a leaf.

Which labelled structure is the xylem?

16 The diagram shows a cross-section of a root.

Three regions of the root are numbered.

Which regions contain cells through which water must pass to reach the xylem?

A 1, 2 and 3 B 1 and 2 only C 2 and 3 only D 2 only

17 In a double circulation, what is the role of the right side of the heart?

A to receive oxygenated blood from the body and to pump oxygenated blood to the lungs
B to receive oxygenated blood from the body and to pump deoxygenated blood to the lungs
C to receive deoxygenated blood from the body and to pump oxygenated blood to the lungs
D to receive deoxygenated blood from the body and to pump deoxygenated blood to the lungs

© UCLES 2022 0610/23/M/J/22

 7

18 The photomicrograph shows some human blood cells.

What is the name of cell X and what is its function?

name function

A lymphocyte produces antibodies

B lymphocyte engulfs pathogens
C phagocyte produces antibodies
D phagocyte engulfs pathogens

19 Three statements about immune responses are listed.

1 Antigens trigger an immune response which produces antibodies.

2 Memory cells are produced.
3 Antibodies are acquired from another individual.

Which statements are correct when describing active immunity?

A 1 only B 1 and 2 only C 2 and 3 only D 1, 2 and 3

20 Which row shows the action of muscles during inspiration?

internal external
diaphragm
intercostal muscles intercostal muscles

A contract relax relax

B contract relax contract
C relax contract relax
D relax contract contract

© UCLES 2022 0610/23/M/J/22 [Turn over

 8

21 Carbon dioxide is produced by aerobic respiration.

How many molecules of carbon dioxide are produced from the aerobic respiration of three
molecules of glucose?

A 3 B 6 C 12 D 18

22 Which statements describe how an oxygen debt is removed after vigorous exercise?

1 Lactic acid is transported to the liver.

2 Lactic acid is respired aerobically.
3 Heart rate stays high to remove lactic acid from the muscles.

A 1 and 2 only B 1 and 3 only C 1, 2 and 3 D 2 and 3 only

23 Which statement about urea is correct?

A Amino acids are transported to the kidneys where they are converted to urea.
B Urea travels from liver cells to the kidneys where it is filtered out of the blood.
C Liver cells break down proteins to amino acids which are then converted to urea in the
kidneys.
D Urea is made in the kidneys and then removed from the body by the liver.

24 The diagram shows the junction between two neurones.

What is labelled at X?

A neurotransmitter
B vesicle
C neurotransmitter receptor molecule
D synaptic cleft

© UCLES 2022 0610/23/M/J/22

 9

25 The diagram shows the density of rods and cones across a section of the retina.

What is the position of the fovea?

cones

rods
density of
receptors

A B C D

distance across the retina

26 What is the synthetic plant hormone 2,4-D used for?

A genetic engineering
B inhibiting phototropism
C killing weeds
D promoting germination

27 Which statement about asexual reproduction would be a disadvantage for a farmer growing crop
plants?

A Desirable qualities are shown throughout the crop.

B No pollinators are required.
C Only one parent plant is required so growth is rapid.
D All of the crop plants have the same risk of disease.

28 The diagram shows an abnormal sperm cell.

Why would the abnormal sperm cell be unable to fertilise an egg?

A It has no acrosome so is unable to digest the jelly coat of the egg.

B It has no mitochondria so lacks energy to swim to the egg.
C It has no flagellum so cannot swim to the egg.
D It has no nucleus so cannot fuse with the egg.

© UCLES 2022 0610/23/M/J/22 [Turn over

 10

29 One type of contraceptive pill contains progesterone and oestrogen. Some effects of the pill are
listed.

1 inhibit FSH production

2 inhibit LH production
3 inhibit thickening of the uterus wall

Which prevent the development and the release of an egg cell?

A 1, 2 and 3 B 1 and 2 only C 2 and 3 only D 3 only

30 Some fruit flies have orange eyes and others have red eyes.

If two orange-eyed fruit flies are crossed, their offspring always have orange eyes.

If two red-eyed fruit flies are crossed, their offspring can have orange eyes or red eyes.

What can be concluded from these observations?

A The allele for orange eyes is dominant.

B The allele for orange eyes is recessive.
C The alleles for orange and red eyes are codominant.
D This is an example of sex linkage.

31 The diagram shows a section of a flower that has been cross-pollinated.

Which statements about this flower are correct?

1 The pollen produced by this flower will be genetically different from the pollen on the
stigma.
2 The pollen was carried to the stigma by wind.
3 This flower is insect-pollinated because the stigma is enclosed by the petals.
4 The pollen was produced by another flower on the same plant.

A 1, 2 and 4 B 1 and 3 C 3 only D 2 and 4 only

© UCLES 2022 0610/23/M/J/22

 11

32 A woman with normal colour vision is a carrier for the colour blindness allele (XBXb). She has a
male child with a man who has normal colour vision (XBY).

What is the chance of the male child being colour-blind?

A 0% B 25% C 50% D 100%

33 Sickle cell anaemia is a genetic disorder which results in severe illness in homozygous
individuals. In some human populations, being heterozygous can be beneficial.

What could be the reason for this?

A Heterozygous individuals are not affected by the disorder.

B Heterozygous individuals are more resistant to malaria.
C The disorder is caused by a dominant allele.
D The disorder is sex-linked.

34 Which statement about selective breeding is correct?

A It does not involve humans.

B It involves a struggle for survival.
C It always involves only one parent.
D It involves parents that possess desirable features.

35 What is the name of an organism that obtains its energy from dead organic material?

A carnivore
B consumer
C decomposer
D herbivore

36 A herd of red deer live in a forest that contains snakes and a large variety of birds.

Which group of organisms is an example of a population?

A all the animals in the forest

B all the red deer in the forest
C all the organisms in the forest
D all the plants in the forest

© UCLES 2022 0610/23/M/J/22 [Turn over

 12

37 With which kingdoms do bacteria share the same genetic code?

A animal, plant, fungus and protoctist

B animal, plant and fungus only
C animal and plant only
D animal only

38 Which process makes use of a genetically engineered organism?

A using bacteria to produce insulin

B using enzymes in biological washing powders
C using pectinase in fruit juice production
D using yeast to produce ethanol

39 What is a reason for conserving plant species?

A to absorb oxygen from the air

B to decrease rainfall
C to obtain drugs for medicinal use
D to release carbon dioxide into the air

40 The food web shows the feeding relationships in a woodland.

sparrowhawks

chaffinches
grey wood
squirrels pigeons

caterpillars

trees

If all the chaffinches in the food web die, which effect would this have?

A The amount of damage to trees will increase.

B The food supply for grey squirrels will increase.
C The number of wood pigeons will increase.
D The population of caterpillars will decrease.

To avoid the issue of disclosure of answer-related information to candidates, all copyright acknowledgements are reproduced online in the Cambridge
Assessment International Education Copyright Acknowledgements Booklet. This is produced for each series of examinations and is freely available to download
at www.cambridgeinternational.org after the live examination series.

© UCLES 2022 0610/23/M/J/22

 Cambridge IGCSE™

BIOLOGY 0610/23
Paper 2 Multiple Choice (Extended) May/June 2023
45 minutes

You must answer on the multiple choice answer sheet.

*4403914185*

You will need: Multiple choice answer sheet

Soft clean eraser
Soft pencil (type B or HB is recommended)

INSTRUCTIONS
 There are forty questions on this paper. Answer all questions.
 For each question there are four possible answers A, B, C and D. Choose the one you consider correct
and record your choice in soft pencil on the multiple choice answer sheet.
 Follow the instructions on the multiple choice answer sheet.
 Write in soft pencil.
 Write your name, centre number and candidate number on the multiple choice answer sheet in the
spaces provided unless this has been done for you.
 Do not use correction fluid.
 Do not write on any bar codes.
 You may use a calculator.

INFORMATION
 The total mark for this paper is 40.
 Each correct answer will score one mark.
 Any rough working should be done on this question paper.

This document has 16 pages. Any blank pages are indicated.

IB23 06_0610_23/4RP
© UCLES 2023 [Turn over
 2

1 What are two characteristics of all living organisms?

A breathing and reproduction

B photosynthesis and excretion
C reproduction and respiration
D respiration and photosynthesis

2 The photograph shows an organism.

Which visible feature can be used to classify this organism as a bird?

A feathers
B lays eggs
C two legs
D wings

© UCLES 2023 0610/23/M/J/23

 3

3 Which statement about cell structure is correct?

A An animal cell has a cell wall.

B A bacterium has a cell wall.
C An animal cell has chloroplasts.
D A bacterium has chloroplasts.

4 The diameter of an egg cell from a frog is 2.5 mm.

The diameter of an egg cell from a human is 120 m.

Which value shows approximately how many times larger an egg cell from a frog is than an egg
cell from a human?

A 2 B 21 C 48 D 300

5 When a plant cell is put into pure water it ......1...... water by osmosis and becomes ......2...... .

Which words should be used to fill gaps 1 and 2 to complete the sentence?

1 2

A gains plasmolysed
B gains turgid
C loses plasmolysed
D loses turgid

6 The graph shows the results of an investigation into the effect of oxygen on the uptake of glucose
by cells.

with oxygen

mass of glucose
taken into cells
no oxygen

time

Which conclusion can be made about these data?

A Glucose only enters the cells by active transport.

B Glucose only enters the cells by diffusion.
C Glucose enters the cells by both active transport and diffusion.
D Glucose enters the cells by osmosis.

© UCLES 2023 0610/23/M/J/23 [Turn over

 4

7 The table shows the results of food tests carried out on a fruit.

Benedict’s ethanol iodine

test biuret
solution emulsion solution
result positive positive negative negative

What did the fruit contain?

A fat and reducing sugar

B fat and starch
C protein and reducing sugar
D protein and starch

8 What describes the structure of DNA?

A Each strand contains chemicals called fatty acids.

B Each strand contains a sequence of amino acids.
C Each strand contains mRNA.
D Two strands coil to form a double helix.

9 The statements are about enzymes.

1 Enzymes are catalysts.

2 Enzymes are proteins.
3 Enzymes are used up during chemical reactions.

Which statements are correct?

A 1, 2 and 3 B 1 and 2 only C 1 and 3 only D 2 and 3 only

10 When the temperature increases, the rate of an enzyme-catalysed reaction increases until the
optimum temperature is reached.

Which statement explains why the rate increases?

A The enzyme and substrate have more kinetic energy and collide less frequently.
B The enzyme and substrate have less kinetic energy and collide more frequently.
C The enzyme and substrate have more kinetic energy and collide more frequently.
D The enzyme and substrate have less kinetic energy and collide less frequently.

© UCLES 2023 0610/23/M/J/23

 5

11 A plant with variegated leaves was placed in a dark cupboard for 48 hours so that all the starch
was removed from the leaves. The variegated leaves have green parts and white parts.

Black paper was then fixed on one leaf and the plant was exposed to the light.

After 24 hours, which region of the leaf contained starch?

green central region white outer region

D
black paper is attached to
both sides of the leaf

12 The graph shows the rate of photosynthesis with increasing light intensity.

rate of 2 3 4
photosynthesis

1
light intensity

Where is light intensity a limiting factor for photosynthesis?

A between 1 and 2
B between 1 and 3
C between 2 and 4
D between 3 and 4

13 In humans, which two components of the diet can be broken down to release energy?

A carbohydrate and fat

B carbohydrate and mineral ions
C protein and water
D vitamins and protein

© UCLES 2023 0610/23/M/J/23 [Turn over

 6

14 Which is a part of the small intestine?

A colon
B ileum
C oesophagus
D rectum

15 Which combination of environmental factors will cause the largest increase in the transpiration
rate in a plant?

wind speed humidity temperature light intensity

A high high low low

B high low high high
C low high low high
D low low high low

© UCLES 2023 0610/23/M/J/23

 7

16 The diagrams represent the movement of substances between plant cells. The arrows indicate
the direction the substance is moving in.

Which diagram of translocation is correctly labelled?

A B

source sink

glucose glucose

sink source
phloem phloem

C D

source sink

sucrose sucrose

sink source
phloem phloem

17 The diagram shows a section of the human heart.

Which label identifies the right ventricle?

D C

© UCLES 2023 0610/23/M/J/23 [Turn over

 8

18 The diagrams show sections through three types of blood vessel. They are not drawn to the
same scale.

1 2 3

In which order will red blood cells flow through these vessels in the human body when travelling
from the aorta to the right atrium of the heart?

A 123 B 132 C 231 D 312

19 When a person is given a vaccine, a harmless pathogen is injected. The pathogen has ......1......
which cause lymphocytes to produce ......2...... . This is an example of ......3...... immunity.

Which words should be used to fill gaps 1, 2 and 3 to complete the sentences?

1 2 3

A antigens antibodies active

B antigens antibodies passive
C antibodies antigens active
D antibodies antigens passive

20 What happens when a person breathes in?

A The external intercostal muscles and the internal intercostal muscles contract.
B The external intercostal muscles and the internal intercostal muscles relax.
C The external intercostal muscles relax and the internal intercostal muscles contract.
D The external intercostal muscles contract and the internal intercostal muscles relax.

© UCLES 2023 0610/23/M/J/23

 9

21 Which graph shows the effect of temperature on enzyme activity?

A B

enzyme enzyme
activity activity

temperature temperature

C D

enzyme enzyme
activity activity

temperature temperature

22 After running a fast race, some students have pains in their leg muscles due to a build up of lactic
acid. A student wrote this explanation.

1 During the race, the cells did not have enough oxygen for aerobic respiration.
2 Anaerobic respiration occurs so some energy is released from glucose.
3 The lactic acid is produced by aerobic respiration.

Which statements explain why the lactic acid built up in the muscles?

A 1 and 2 B 1 only C 2 and 3 D 3 only

23 What is the name of the process that produces urea and the organ where urea is formed?

process organ where

producing urea urea is formed

A deamination kidney
B denitrification kidney
C deamination liver
D denitrification liver

© UCLES 2023 0610/23/M/J/23 [Turn over

 10

24 The diagram shows the gap between two neurones.

What is the name of X?

A neurotransmitter
B receptor
C synapse
D vesicle

25 Which statements are correct for cone cells in the eye?

1 Cone cells are located in the fovea of the retina.

2 Cone cells detect colour.
3 Cone cells are more sensitive to light than rod cells.

A 1, 2 and 3 B 1 and 2 only C 1 and 3 only D 2 and 3 only

26 The diagram shows the structure of the human skin.

Which structure constricts to reduce heat loss?

© UCLES 2023 0610/23/M/J/23

 11

27 Where are the hormones oestrogen and progesterone produced during pregnancy?

A amniotic sac
B oviducts
C placenta
D umbilical cord

28 The umbilical artery takes blood from the fetus to the placenta.

The umbilical vein carries blood from the placenta to the fetus.

How do the contents of the umbilical artery differ from those of the umbilical vein?

carbon dioxide oxygen urea

A less more less

B less less more
C more more less
D more less more

29 Which row shows some of the features involved in natural selection?

humans choose alleles are

many offspring
desirable passed onto
are produced
features offspring

A key
B = yes
C = no
D

30 Which substance is coded for by a length of DNA?

A base
B glucose
C glycerol
D lipase

© UCLES 2023 0610/23/M/J/23 [Turn over

 12

31 The diagram shows the sex chromosomes of a woman and of a man. Their genotypes for a
recessive sex-linked condition are also shown.

A a a key
A is dominant
a is recessive

What are the chances that their daughter will show the sex-linked condition?

A 0% B 25% C 50% D 75%

32 Which Punnett square shows a test cross that identifies a heterozygous parent?

A B C D

T t T T T t T T

T TT Tt T TT TT t Tt tt t Tt Tt

t Tt tt t Tt Tt t Tt tt t Tt Tt

33 What is a definition of variation?

A having two identical alleles of a particular gene

B individuals of the same species in one area
C differences between individuals of the same species
D the way in which new alleles are formed

34 What is a feature of some xerophytes?

A large air spaces in the tissues

B leaves rolled up and covered with hairs
C leaves with stomata on the upper surface
D thin cuticle

35 Where does the energy being transferred along a food chain originally come from?

A producer
B photosynthesis
C carbon dioxide
D the Sun

© UCLES 2023 0610/23/M/J/23

 13

36 Which diagram shows a pyramid of biomass for a forest?

A B

C D

37 Which substance is an enzyme used in fruit juice production?

A lactase
B maltose
C pectinase
D pepsin

38 The diagram shows some of the effects of human activity on a river.

bacteria use up
dissolved oxygen

aquatic plants
grow quickly fish die from
lack of oxygen

What could have caused these effects?

A air pollution
B deforestation
C over-use of fertilisers
D presence of herbicides

© UCLES 2023 0610/23/M/J/23 [Turn over

 14

39 Genetic modification has been used to produce human insulin in bacterial cells.

What is inserted into the bacterial cells to produce human insulin?

A a human nucleus
B human plasmids
C recombinant insulin
D recombinant plasmids

40 Penicillin is made in a fermenter by growing organisms.

Which type of organism is used in the production of penicillin?

A bacterium
B fungus
C protoctist
D virus

© UCLES 2023 0610/23/M/J/23

 Cambridge International Examinations
Cambridge International General Certificate of Secondary Education

BIOLOGY 0610/23
Paper 2 Multiple Choice (Extended) October/November 2017
45 minutes
Additional Materials: Multiple Choice Answer Sheet
Soft clean eraser
*0288685329*

Soft pencil (type B or HB is recommended)

READ THESE INSTRUCTIONS FIRST

Write in soft pencil.

Do not use staples, paper clips, glue or correction fluid.
Write your name, Centre number and candidate number on the Answer Sheet in the spaces provided
unless this has been done for you.
DO NOT WRITE IN ANY BARCODES.

There are forty questions on this paper. Answer all questions. For each question there are four possible
answers A, B, C and D.
Choose the one you consider correct and record your choice in soft pencil on the separate Answer Sheet.

Read the instructions on the Answer Sheet very carefully.

Each correct answer will score one mark. A mark will not be deducted for a wrong answer.
Any rough working should be done in this booklet.
Electronic calculators may be used.

The syllabus is approved for use in England, Wales and Northern Ireland as a Cambridge International Level 1/Level 2 Certificate.

This document consists of 17 printed pages and 3 blank pages.

IB17 11_0610_23/3RP
© UCLES 2017 [Turn over
 2

1 The plant Mimosa pudica has leaves that fold in when touched.

This demonstrates movement and which other characteristic?

A excretion
B growth
C nutrition
D sensitivity

2 The diagram shows a section of DNA from a chimpanzee.

A G C T A C A G A G

Which diagram shows a section of DNA from the organism that is most closely related to the
chimpanzee?

A A G C T A C A G A T

B A G C T A C A G T T

C A T C A A C A G T T

D A T C T A C A G T T

© UCLES 2017 0610/23/O/N/17

 3

3 The diagrams show structures associated with a leaf.

thick cellulose wall

nucleus

vacuole

cytoplasm
leaf leaf stalk detail

What is the level of organisation of the part shown in detail?

A cell
B organ
C organ system
D tissue

4 The diagram shows a pollen grain of a rice plant. The size of the image is 40 mm

40 µm

The actual length of the pollen grain is 40 µm.

By how many times has the diagram been magnified?

A ×1 B ×10 C ×100 D ×1000

© UCLES 2017 0610/23/O/N/17 [Turn over

 4

5 Three equally sized pieces of potato were put into different concentrations of sucrose solution.
One piece of potato was put into distilled water.

The concentrations of sucrose solution were 0.2 g dm–3, 0.4 g dm–3 and 0.6 g dm–3.

The graph shows the change in mass of the potato pieces over a period of 60 minutes.

Which piece of potato was put into distilled water?

2
A
change in mass of 1 B
the potato pieces / g
0 C
0 time / minutes 60
–1 D

6 A red blood cell and a palisade mesophyll cell are placed in a solution which has a higher water
potential than the cells.

What will happen to each cell?

palisade
red blood cell
mesophyll cell

A bursts bursts
B bursts gains mass
C loses mass gains mass
D loses mass loses mass

© UCLES 2017 0610/23/O/N/17

 5

7 The diagram shows an evolutionary tree based on a computer-generated study of different sea
mammals.

fin whale

humpback whale

sperm whale

beaked whale
common ancestor
dolphin

porpoise

According to this evolutionary tree, which whale has DNA base sequences that are least shared
with the other whales?

A beaked whale
B fin whale
C humpback whale
D sperm whale

8 What is the colour change shown by Benedict’s solution when heated with a reducing sugar?

A blue to purple
B blue to red
C brown to blue-black
D red to yellow

© UCLES 2017 0610/23/O/N/17 [Turn over

 6

9 Into which part of the alimentary canal is the enzyme that digests starch secreted?

10 The diagram shows an enzyme with its substrate and product molecules.

Q
P

Which form an enzyme-substrate complex?

A P and Q B Q and R C R and S D S and P

© UCLES 2017 0610/23/O/N/17

 7

11 The diagram shows the apparatus at the beginning of an investigation into temperature change
during the germination of seeds. The temperature at the start of the investigation was 25 °C in
both flasks.

After two days the temperature in flask 1 is 25 °C. The temperature in flask 2 is 28 °C.

vacuum
flask

dead and living seeds

disinfected
seeds

cotton wool

thermometer

flask 1 flask 2

Which characteristic of living organisms is shown in this experiment?

A excretion
B growth
C reproduction
D respiration

12 What must be increased in the diet of a person suffering from constipation?

A fats
B fibre
C iron
D protein

© UCLES 2017 0610/23/O/N/17 [Turn over

 8

13 Which substrate, enzyme and product are correctly named?

substrate enzyme product

A amino acids trypsin protein

B amylase maltose glucose
C lipase lipid fatty acids and glycerol
D maltose maltase glucose

14 The diagram shows the human alimentary canal, with a string marked in metres beside it.

oesophagus
0

3
string marked
in metres
4

9 anus

How long is the small intestine?

A 2m B 6m C 8m D 9m

© UCLES 2017 0610/23/O/N/17

 9

15 What is not a use of water by plants?

A acting as a solvent
B cooling the plant
C dissolving cellulose cell walls
D raw material in photosynthesis

16 What is a description of transpiration?

A exchange of gases between the leaf and the atmosphere

B loss of water vapour from the leaves and stems of a plant
C movement of water from the roots to the leaves
D movement of water through the cells of the leaf

17 The diagram represents the circulatory system of a mammal.

In which chamber of the heart are the muscle walls thickest?

rest of
lungs A B body

D C

heart

© UCLES 2017 0610/23/O/N/17 [Turn over

 10

18 The diagram shows a cross-section through a human blood vessel.

elastic and fibrous

connective tissue

muscle layer

Which type of blood vessel does the diagram show?

A an artery
B a capillary
C a vein
D a ventricle

19 What can be passed from one person to another during blood transfusion?

A cholera
B chronic obstructive pulmonary disease (COPD)
C HIV
D scurvy

20 The table shows some of the changes that occur during breathing.

from contracted from relaxed

to relaxed to contracted

diaphragm P X
external intercostals Q Y
internal intercostals R Z

Which changes occur to cause inspiration?

A P, Q and Z B X, Q and R C X, Y and R D X, Y and Z

© UCLES 2017 0610/23/O/N/17

 11

21 In an experiment to investigate anaerobic respiration, two bottles are set up in a warm room, as
shown.

P Q
balloon balloon

sugar, yeast yeast

and water and water

What would happen to each balloon after one day?

A B

P Q P Q

C D

P Q P Q

© UCLES 2017 0610/23/O/N/17 [Turn over

 12

22 Two pieces of an aquatic plant were placed into two different test-tubes, P and Q.

Each test-tube contained hydrogencarbonate indicator and was sealed and kept at 20 °C.

Test-tube P was kept in the light and test-tube Q was kept in the dark.

The table shows the effect of carbon dioxide on the colour of the hydrogencarbonate indicator.

less carbon more carbon

dioxide dioxide

dark red orange

What would the colour of the indicator be after 12 hours?

P Q

A dark red orange

B dark red dark red
C orange dark red
D orange orange

23 What is the most important function of sweating?

A to remove excess heat from the body

B to remove excess salts from the body
C to remove excess urea from the body
D to remove excess water from the body

24 A student begins to lose control of her bicycle while travelling down a hill at speed.

The concentration of which substance will begin to increase rapidly in her blood?

A adrenaline
B insulin
C oestrogen
D testosterone

© UCLES 2017 0610/23/O/N/17

 13

25 The diagram shows a person sweating in hot weather.

What part is played by sweat glands during the process of sweating?

A effector
B receptor
C sense organ
D stimulus

26 The diagram shows a synapse in a reflex arc.

P Q

What are the identities of the two neurones and in which direction does the neurotransmitter
pass?

direction of passage
neurone P neurone Q
of neurotransmitter

A motor relay P→Q

B motor sensory P→Q
C relay motor Q→P
D relay sensory Q→P

27 Which process occurring at a synapse is prevented by the presence of heroin?

A the binding of a neurotransmitter with receptors

B the diffusion of a neurotransmitter across the gap
C the formation of a neurotransmitter
D the stimulation of vesicles by an impulse

© UCLES 2017 0610/23/O/N/17 [Turn over

 14

28 The diagram shows half a flower.

Q
R

After pollination, where would pollen grains be found?

A P and Q B Q and R C R and S D S and P

29 Which environmental factor is not always a requirement for seed germination?

A light
B oxygen
C suitable temperature
D water

30 A pure-breeding white rat was crossed with a pure-breeding black rat. All their offspring were
black.

One of the offspring was bred with a pure-breeding white rat.

What is the most likely percentage of black rats in the offspring?

A 25 B 50 C 75 D 100

31 An organism is heterozygous for a gene with the alleles T and t.

Which diagram represents a diploid cell from this organism?

A B C D

T t T T t T

© UCLES 2017 0610/23/O/N/17

 15

32 Red-green colour blindness is a sex-linked characteristic caused by a recessive allele.

Which prediction can be made about the children of a woman who is colour-blind and a man with
normal vision?

A Boys will be colour-blind, girls will have a 50% chance of being colour-blind.
B Boys will be colour-blind, girls will have normal vision.
C Girls will be colour-blind, boys will have a 50% chance of being colour-blind.
D Girls will be colour-blind, boys will have normal vision.

33 The diagram shows a vertical section through a leaf.

upper epidermis

sub-stomatal
air chamber

spongy
mesophyll cell

lower epidermis

Which diagram shows the plant that the leaf was taken from?

A B C D

water

34 What is a mutation?

A a change in appearance
B a change in a gene
C a change in behaviour
D a change in the environment

© UCLES 2017 0610/23/O/N/17 [Turn over

 16

35 The biomass at each trophic level in an ecosystem is measured. The results are shown in the
table.

Which trophic level contains herbivores?

trophic
mass / g m–3
level

A 0.1
B 0.6
C 1.2
D 17.9

36 The diagram shows a food web.

plants herbivores carnivores

decomposers

What do the arrows represent?

A the absorption of oxygen

B the absorption of water
C the flow of energy
D the release of carbon dioxide

37 Ligase enzymes are used in genetic engineering to

A cut open plasmid DNA.

B insert plasmids into bacteria.
C isolate the DNA making up a human gene.
D join human DNA to plasmid DNA.

38 With which kingdoms do bacteria share the same genetic code?

A animal, plant, fungus and protoctist

B animal, plant and fungus only
C animal and plant only
D animal only

© UCLES 2017 0610/23/O/N/17

 17

39 What is a direct result of deforestation?

A decreased leaching of mineral salts

B increased loss of soil
C increased production of methane
D increased recycling of important minerals

40 The table shows the ability of three species of fish and their eggs to survive in water at different
pH levels.

If the eggs do not survive offspring cannot be produced.

pH
6.5 6.0 5.5 5.0 4.5 4.0

trout key
sea bass = survive
perch = do not survive
fish eggs

A lake at pH 6.0 contains breeding populations of all three fish.

If acid rain causes the pH to fall to 5.0, which outcome would be likely to occur?

A Trout and perch will survive and produce offspring.

B Trout and perch will survive but only perch will produce offspring.
C Trout and perch will survive but produce no offspring.
D Trout, sea bass and perch will survive but produce no offspring.

© UCLES 2017 0610/23/O/N/17

 Cambridge International Examinations
Cambridge International General Certificate of Secondary Education

BIOLOGY 0610/23
Paper 2 Multiple Choice (Extended) October/November 2018
45 minutes
Additional Materials: Multiple Choice Answer Sheet
Soft clean eraser
*6778270274*

Soft pencil (type B or HB is recommended)

READ THESE INSTRUCTIONS FIRST

Write in soft pencil.

Do not use staples, paper clips, glue or correction fluid.
Write your name, Centre number and candidate number on the Answer Sheet in the spaces provided
unless this has been done for you.
DO NOT WRITE IN ANY BARCODES.

There are forty questions on this paper. Answer all questions. For each question there are four possible
answers A, B, C and D.
Choose the one you consider correct and record your choice in soft pencil on the separate Answer Sheet.

Read the instructions on the Answer Sheet very carefully.

Each correct answer will score one mark. A mark will not be deducted for a wrong answer.
Any rough working should be done in this booklet.
Electronic calculators may be used.

This syllabus is approved for use in England, Wales and Northern Ireland as a Cambridge International Level 1/Level 2 Certificate.

This document consists of 18 printed pages and 2 blank pages.

IB18 11_0610_23/4RP
© UCLES 2018 [Turn over
 2

1 The Venus flytrap is a plant that feeds on insects. When a fly lands on the leaf, the leaf folds very
quickly and traps the fly. The leaves produce enzymes which digest the fly.

Which characteristics of living organisms are involved?

A excretion, growth, nutrition

B movement, excretion, nutrition
C movement, sensitivity, growth
D movement, sensitivity, nutrition

2 The diagrams show four organisms not drawn to the same scale.

Which organism is a prokaryote?

A B

not to
scale
C D

3 Sunflowers have yellow flowers.

Which cell structure is found in sunflower leaves but not in the petals of the flowers?

A cell membrane
B cell wall
C chloroplast
D vacuole

© UCLES 2018 0610/23/O/N/18

 3

4 The diagram shows part of a leaf in cross-section.

Structures X and Y are both part of the same

A cell.
B organ.
C tissue.
D vessel.

5 How do carbon dioxide and oxygen move into and out of a mesophyll cell?

A active transport
B diffusion
C respiration
D transpiration

6 Which process is involved in the uptake of glucose by the epithelial cells of kidney tubules?

A active transport
B diffusion
C osmosis
D transpiration

© UCLES 2018 0610/23/O/N/18 [Turn over

 4

7 The data show the concentrations of sugar and starch in an onion.

total sugar including

starch
reducing sugar
/ g per 100g
/ g per 100g

3.7 0.0

The onion is tested with Benedict’s solution and iodine solution.

Which set of results is correct?

Benedict’s iodine
solution solution

A blue blue-black
B blue brown
C brick red blue-black
D brick red brown

8 Which processes depend on the fact that water is a solvent?

evaporation glucose
movement of water loss of sweat from
from the spongy transported
by osmosis the skin surface
mesophyll cells in blood plasma

A
B
C
D

© UCLES 2018 0610/23/O/N/18

 5

9 The apparatus shown is used for an experiment on starch digestion.

Which test-tube contains the most sugar after 20 minutes?

A B C D

starch starch
solution starch solution
and salivary solution and salivary
amylase amylase

water-bath at 15 °C water-bath at 37 °C

10 The graph shows how an enzyme-controlled reaction is affected by temperature.

X
6
5
4
rate
/ arbitrary 3
units
2 Y
1
0
0 10 20 30 40 50
temperature / °C

Which statement explains the change in activity between X and Y?

A There are more effective collisions.

B There is a change in the enzyme shape.
C There is more substrate present.
D The kinetic energy of the molecules has increased.

© UCLES 2018 0610/23/O/N/18 [Turn over

 6

11 An experiment was carried out using the apparatus shown.

The carbon dioxide content of the water in each test-tube was measured at the start and again
three hours later.

In which test-tube would there be a decrease in carbon dioxide content?

A B C D

black
water polythene
to keep
out light light light light
water
plant

water
snail

12 Which region in the leaf of a green plant contains phloem?

A palisade mesophyll
B spongy mesophyll
C upper epidermis
D vascular bundle

13 What is the result of a diet lacking iron?

A bleeding gums
B poor wound healing
C reduced number of red blood cells
D weak bones and teeth

© UCLES 2018 0610/23/O/N/18

 7

14 The diagram shows the activity of salivary amylase, pancreatic lipase and stomach protease at
different pH levels.

enzyme
activity

1 2 3 4 5 6 7 8 9 10 11 12
pH

From the graph, what is the optimum pH for the protease enzyme?

A 2.0 B 3.5 C 7.0 D 8.0

15 The diagram shows a section through the stem of a dicotyledonous plant.

Which part transports water and mineral ions?

© UCLES 2018 0610/23/O/N/18 [Turn over

 8

16 Roots and leaves both act as a source and a sink for sucrose and amino acids at different times
during the year.

At which point in the year are the roots most active as a source?

A
spring
new leaves
start to grow

D B
winter summer
no leaves leaves are
are present mature

C
autumn
leaves die
and fall

17 The diagram shows a circulatory system.

2 3

capillaries of capillaries of the

the lungs heart rest of the body

1 4

Which vessels carry oxygenated blood?

A 1 and 2 B 1 and 4 C 2 and 3 D 2 and 4

18 What happens to the heart valves when the ventricles contract?

atrioventricular semilunar
valves valves

A valves close valves close

B valves close valves open
C valves open valves close
D valves open valves open

© UCLES 2018 0610/23/O/N/18

 9

19 The diagram with the structure labelled X shows a bacterium with proteins on its surface. The
diagram labelled Y shows proteins made by the human body.

Which row shows the correct combination for destroying the bacterium?

correct
name of X name of Y
shape of Y

A antigen antibody

B antibody antigen

C antigen antibody

D antibody antigen

© UCLES 2018 0610/23/O/N/18 [Turn over

 10

20 The graph shows changes in the volume of air in the lungs of a person at rest, over a period of 30
seconds.

2
volume
of air in
lungs 1
/ dm3
0
0 30
time / s

Which graph shows changes in the volume of air in the lungs of the same person immediately
after they have done five minutes of vigorous exercise?

A B
2 2
volume volume
of air in of air in
lungs 1 lungs 1
/ dm3 / dm3
0 0
0 30 0 30
time / s time / s

C D
2 2
volume volume
of air in of air in
lungs 1 lungs 1
/ dm3 / dm3
0 0
0 30 0 30
time / s time / s

21 Glucose is required for respiration.

Which other molecule is required for aerobic respiration?

A carbon dioxide
B nitrogen
C oxygen
D water

© UCLES 2018 0610/23/O/N/18

 11

22 Which row correctly shows the organ where each substance is excreted?

carbon dioxide excess water salts urea

A kidneys liver lungs lungs

B liver liver liver skin
C lungs kidneys kidneys kidneys
D lungs kidneys liver skin

23 The diagram shows the appearance of the iris and pupil in three different light conditions.

1 2 3
iris

pupil

Which row shows the size of the pupil of the eye in each light condition?

no moderate bright
light light light

A 1 2 3
B 1 3 2
C 2 1 3
D 3 2 1

© UCLES 2018 0610/23/O/N/18 [Turn over

 12

24 A student used two seedlings X and Y to investigate phototropism.

The diagram shows their investigation.

light light
piece of glass piece of glass

X X
at the start of after some time
the experiment no curvature towards light

light light

piece of glass piece of glass

Y Y
at the start of after some time
the experiment gives curvature towards light

Which statement explains the difference in results between X and Y?

A The piece of glass destroyed the auxin on the shaded side of the seedling.
B The piece of glass destroyed the auxin on the side of the seedling facing the light.
C The piece of glass in X stopped the auxin travelling down the shaded side of the seedling.
D The piece of glass in X stopped the auxin travelling down the side of the seedling facing the
light.

25 In a mammal, body temperature is regulated by negative feedback.

As a result of negative feedback, what happens in the mammal’s body as the temperature of the
external environment decreases?

A relaxation of hair erector muscles

B sweating
C vasoconstriction
D vasodilation

© UCLES 2018 0610/23/O/N/18

 13

26 The graph shows the number of cases of MRSA in one country between 2001 and 2006.

8000

7250
number of
cases of 6500
MRSA
5750

5000
2001 2002 2003 2004 2005 2006
year

Between which years was the greatest change in the number of cases of MRSA seen?

A 2002 and 2003

B 2003 and 2004
C 2004 and 2005
D 2005 and 2006

27 Pollen grains are transferred from the anthers to the stigma. The pollen grains adhere to the
sticky stigma. The statements describe what happens next.

1 The pollen grain grows a pollen tube.

2 The pollen tube enters the ovule.
3 The pollen tube grows down the style.
4 The male nucleus fuses with an egg cell nucleus.

In which order do these stages occur?

A 1→2→4→3

B 1→3→2→4

C 2→3→1→4

D 3→1→4→2

© UCLES 2018 0610/23/O/N/18 [Turn over

 14

28 The diagram shows a woman’s menstrual cycle.

bleeding bleeding
starts stops

day day
0 28

P QR S

On which day does ovulation occur, and on which day could fertilisation occur?

ovulation fertilisation

A P R
B P S
C Q R
D Q S

29 Which method of contraception could also help prevent the spread of HIV?

A condom
B contraceptive pill
C monitoring cervical mucus
D vasectomy

30 Which name is given to different versions of a gene?

A allele
B chromosome
C length of DNA
D protein

31 Which feature of meiosis ensures that the zygote is diploid?

A Chromosomes are duplicated.

B Four gametes are formed.
C Genetically different gametes are formed.
D Haploid gametes are formed.

© UCLES 2018 0610/23/O/N/18

 15

32 Which genotypes result in a person having blood group A?

A IAIA and IAIB B IAIA and IAIo C IAIo and IoIo D IAIo and IAIB

33 The diagram shows a plant reproducing asexually by growing a plantlet from a runner. The
leaves of the plantlet appear different to the leaves of the parent plant.

parent plant

runner

plantlet

Which statement explains the difference in the leaf shape of the plantlet?

A A mutation has occurred in the genes of the plantlet.

B The plantlet inherited the genes from the parent plant.
C The plant was produced by meiosis.
D The plantlet was produced by the fusion of gametes.

34 What results from the process of natural selection and adaptation?

A artificial selection
B evolution
C reproduction
D selective breeding

© UCLES 2018 0610/23/O/N/18 [Turn over

 16

35 The diagram shows a food web in the ocean.

shark

penguin seal

krill herring

algae

Which two animals are secondary and tertiary consumers?

A penguin and herring

B penguin and shark
C seal and penguin
D seal and shark

© UCLES 2018 0610/23/O/N/18

 17

36 A student was given data on the change in the number of insects in a population over a period of
twelve weeks. The student was asked to name and label each phase.

phase
one phase two phase three
13
12
11
10
9
8
number
7
of insects
/ thousand 6
5
4
3
2
1
0
0 1 2 3 4 5 6 7 8 9 10 11 12
time / weeks

What is the correct label for phase three?

A death phase
B exponential (log) phase
C lag phase
D stationary phase

37 Insulin is now produced using genetically modified bacteria. Previously, diabetics were given
insulin extracted from the pancreas of animals.

Why is the insulin from bacteria regarded as a better ethical choice?

A insulin is produced from bacterial DNA

B it is accepted by vegetarians
C plasmids are involved
D the genetic code is shared

© UCLES 2018 0610/23/O/N/18 [Turn over

 18

38 Plasmids are often used in genetic engineering.

What is a plasmid?

A bacterial cell
B gene
C loop of DNA
D protein

39 The diagram shows a food web in a woodland.

hawks

hedgehogs blackbirds sparrows hornets

snails caterpillars

tree type X tree type Y

What is most likely to happen if all of tree type X is removed by humans?

A The carbon dioxide concentration in the woodland will decrease.

B The population of hedgehogs will increase.
C The population of hornets will increase.
D The population of sparrows will decrease.

40 The increased availability of nitrates in rivers and lakes can result in the death of fish.

Which statement explains why fish die in rivers and lakes containing a high concentration of
nitrates?

A The increase in water plants stops the fish swimming.

B There is an increase in anaerobic respiration by plants.
C There are fewer water plants for fish to eat.
D There is an increase in aerobic respiration by decomposers.

© UCLES 2018 0610/23/O/N/18

 Cambridge Assessment International Education
Cambridge International General Certificate of Secondary Education

BIOLOGY 0610/23
Paper 2 Multiple Choice (Extended) October/November 2019
45 minutes
Additional Materials: Multiple Choice Answer Sheet
Soft clean eraser
*6635924783*

Soft pencil (type B or HB is recommended)

READ THESE INSTRUCTIONS FIRST

Write in soft pencil.

Do not use staples, paper clips, glue or correction fluid.
Write your name, centre number and candidate number on the Answer Sheet in the spaces provided
unless this has been done for you.
DO NOT WRITE IN ANY BARCODES.

There are forty questions on this paper. Answer all questions. For each question there are four possible
answers A, B, C and D.
Choose the one you consider correct and record your choice in soft pencil on the separate Answer Sheet.

Read the instructions on the Answer Sheet very carefully.

Each correct answer will score one mark. A mark will not be deducted for a wrong answer.
Any rough working should be done in this booklet.
Electronic calculators may be used.

This syllabus is regulated for use in England, Wales and Northern Ireland as a Cambridge International Level 1/Level 2 Certificate.

This document consists of 16 printed pages.

IB19 11_0610_23/5RP
© UCLES 2019 [Turn over
 2

1 The diagrams show a plant at the start of an experiment, and the same plant two weeks later.

light from
one side

start of experiment after two weeks

Which characteristics of living organisms are demonstrated by this experiment?

A excretion, growth, movement

B excretion, movement, reproduction
C growth, movement, sensitivity
D sensitivity, growth, respiration

2 Donkeys and zebras are different species. They can breed to produce an animal called a zedonk.

Zedonks are not fertile.

Which statement is correct?

A Zedonks and donkeys are the same species.

B Zedonks and zebras are the same species.
C Zedonks are a species.
D Zedonks are not a species.

3 Which feature is characteristic only of birds?

A hair and wings

B hard-shelled eggs and feathers
C scales and soft-shelled eggs
D wings and soft-shelled eggs

© UCLES 2019 0610/23/O/N/19

 3

4 Which features do animal cells share with plant cells?

chloroplast cytoplasm nucleus

A key
B = yes
C = no
D

5 A bacterium is 0.5 µm long.

A student makes a drawing of the bacterium. The student’s drawing is 100 mm long.

What is the magnification of the student’s drawing?

A ×0.005 B ×50 C ×200 D ×200 000

6 Red blood cells were placed in pure water.

Movement of water across the cell membrane caused a change in their appearance.

What caused this change in appearance?

direction of from higher to lower from lower to higher

water movement water potential water potential

A into cells yes no

B into cells no yes
C out of cells yes no
D out of cells no yes

© UCLES 2019 0610/23/O/N/19 [Turn over

 4

7 The diagram shows a root hair cell.

cytoplasm
vacuole

mitochondria
nucleus

Why does a root hair cell contain a large number of mitochondria?

A to provide energy for the absorption of water from the soil

B to provide energy for the diffusion of mineral ions from the soil
C to provide energy for osmosis
D to provide energy for the active transport of mineral ions from the soil

8 Which identifies the chemical elements found in proteins?

carbon hydrogen oxygen nitrogen

A key
B = present
C = absent
D

9 Enzyme X digests protein in the stomach.

Four test-tubes were set up, each contained the same amounts of protein and enzyme X. The
test-tubes are kept at different levels of pH and temperature, as shown in the table.

In which test-tube will protein digestion be quickest?

pH temperature / °C

A 2 20
B 2 35
C 7 20
D 7 35

© UCLES 2019 0610/23/O/N/19

 5

10 Which substance is used up in photosynthesis?

A chlorophyll
B light
C oxygen
D water

11 The diagram shows a leaf as seen in cross-section under the microscope.

What are tissues 1, 2 and 3?

1 2 3

A epidermis palisade mesophyll spongy mesophyll

B epidermis spongy mesophyll palisade mesophyll
C palisade mesophyll epidermis spongy mesophyll
D spongy mesophyll palisade mesophyll epidermis

12 The pie charts show the composition of 100 g of four different foods.

Which food provides the most energy?

A B C D
key
carbohydrate
fats and oils
protein
water

© UCLES 2019 0610/23/O/N/19 [Turn over

 6

13 Cholera is a disease caused by a bacterium called Vibrio cholerae which produces a toxin in the
infected person’s gut.

What is the effect of this toxin?

A It causes loss of water from the gut into the blood.

B It causes loss of water from the gall bladder into the blood.
C It causes water to enter the gut from the blood.
D It causes water to enter the gall bladder from the blood.

14 The diagram shows an experiment kept at room temperature.

tubing containing
starch, protease, test-tube
protein and simple
sugars
distilled water

membrane permeable
to small molecules only

What is present in the water surrounding the membrane after 45 minutes?

A amino acids and simple sugars

B protein and amino acids
C protein and simple sugars
D starch and simple sugars

© UCLES 2019 0610/23/O/N/19

 7

15 The diagram shows a cross-section through a plant root.

What is found at Q and R?

Q R

A palisade mesophyll spongy mesophyll

B phloem xylem
C spongy mesophyll palisade mesophyll
D xylem phloem

16 Rabbits can damage trees by eating the bark and phloem.

leaves

bark

remaining stem

bark

roots

If the damage goes all the way around the stem, what will happen in the tree?

A Sugars cannot move from the leaves to the roots causing swelling above the ring.
B Sugars cannot move from the leaves to the roots causing swelling below the ring.
C Water cannot move from the leaves to the roots causing swelling above the ring.
D Water cannot move from the leaves to the roots causing swelling below the ring.

© UCLES 2019 0610/23/O/N/19 [Turn over

 8

17 The table shows the concentration of red blood cells, white blood cells and platelets in the blood
of four patients.

Which patient is most likely to have a deficiency of iron in their diet and will find it difficult to form
a blood clot?

red blood cells white blood cells platelets

/ cells per mm3 / cells per mm3 / cells per mm3

A 2 525 000 643 296 000

B 2 275 000 756 27 500
C 7 250 000 650 275 000
D 7 325 000 405 25 000

18 Which row describes the features of passive immunity?

antibodies involves effective

made memory cells period

A no no short term
B no yes short term
C yes no long term
D yes yes long term

19 What is the sequence of structures through which a molecule of oxygen passes from the air to
the blood of a person?

1 bronchiole
2 capillary
3 alveolus wall
4 larynx

A 1→4→2→3

B 3→2→1→4

C 4→1→3→2

D 4→2→1→3

© UCLES 2019 0610/23/O/N/19

 9

20 How do green plants and mammals obtain their energy?

green plants mammals

A from the soil from sleeping and resting

B from the air around the plant from the air they breathe
C from the Sun from digested and absorbed food
D from water and carbon dioxide from water and oxygen

21 Lactic acid builds up in the muscles during vigorous exercise.

During recovery, how is this lactic acid removed?

A aerobic respiration of lactic acid in the liver

B anaerobic respiration of lactic acid in the muscles
C excretion of lactic acid by the lungs
D removal of lactic acid by the alimentary canal

22 The diagram shows a synapse.

neurone 1

neurone 2

Heroin is a drug that can bind with receptors in a synapse.

What is the most likely effect heroin will have on the synapse?

A cause the impulse to travel back along neurone 1

B prevent neurotransmitter binding with receptors on neurone 2
C stop the impulse being generated in neurone 1
D transfer the impulse to a different neurone other than neurone 2

© UCLES 2019 0610/23/O/N/19 [Turn over

 10

23 The diagram shows the muscles that control the size of the pupil in an eye.

iris
circular muscles

radial muscles

pupil

How do the muscles make the pupil smaller?

circular muscles radial muscles

A contract contract
B contract relax
C relax contract
D relax relax

24 In a plant shoot, where is auxin made and what is its effect?

where made effect

A leaves promotes cell division

B leaves promotes cell elongation
C shoot tip promotes cell division
D shoot tip promotes cell elongation

© UCLES 2019 0610/23/O/N/19

 11

25 A patient has dye injected into the blood supply to his kidneys. The dye appears in his excretory
system as shown.

key
dye
no dye

Which part is blocked?

A the kidney
B the ureter
C the bladder
D the urethra

26 Which statement about antibiotics is correct?

A Antibiotics are used to treat all transmissible diseases.

B Antibiotics are used to treat diseases caused by viruses.
C Antibiotic resistance can be stopped by increasing their use.
D Antibiotics are used to treat diseases caused by bacteria.

27 Which substance in tobacco smoke directly reduces the oxygenation of blood?

A carbon dioxide
B carbon monoxide
C nicotine
D tar

© UCLES 2019 0610/23/O/N/19 [Turn over

 12

28 The concentrations of LH and oestrogen are measured during part of a menstrual cycle.

On which day does ovulation occur?

day from concentration concentration

start of of LH of oestrogen
menstrual cycle / arbitrary units / arbitrary units

A 7 10 30
B 10 12 135
C 13 120 130
D 16 20 25

29 Where are oestrogen and progesterone produced during the menstrual cycle in a woman who is
not pregnant?

oestrogen progesterone

A adrenal gland ovary

B ovary ovary
C ovary placenta
D placenta pancreas

30 A haploid nucleus is defined as one that contains

A one chromosome.
B one set of unpaired chromosomes.
C two chromosomes.
D two sets of chromosomes.

© UCLES 2019 0610/23/O/N/19

 13

31 The diagram shows a diploid cell and alleles R and r on one pair of chromosomes.

nucleus R
r
cytoplasm

When this cell divides by mitosis, which daughter cells will be produced?

chromosome number genotype

A diploid heterozygous
B diploid homozygous
C haploid heterozygous
D haploid homozygous

32 Sickle-cell anaemia is caused by a mutation in the haemoglobin gene.

The normal base sequence is shown in 1, and the sickle-cell base sequence is shown in 2.

1 TGA GGA CTC CTC

2 TGA GGA CAC CTC

What causes the change in the DNA?

A the addition of one base

B the addition of two bases
C the change of one base for another
D the deletion of one base

© UCLES 2019 0610/23/O/N/19 [Turn over

 14

33 The diagram shows part of a section through the leaf of a water lily.

Their leaves are adapted to help them to live on the surface of the water.

How is the leaf of this plant adapted to being a hydrophyte?

A It does not have a cuticle.

B It has a palisade layer.
C It has an epidermis.
D It has stomata on upper surface.

34 What could be responsible for the conversion of nitrogen in the atmosphere to nitrates in the soil?

A decomposers
B denitrifying bacteria
C lightning
D nitrifying bacteria

35 Which statement describes the effect of a disease which kills members of a population?

A It causes an exponential (log) increase in the population size.

B It decreases the rate of growth of the population.
C It decreases the food supply available to the population.
D It reduces the lag phase of the population.

© UCLES 2019 0610/23/O/N/19

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36 The diagram shows a pyramid of numbers in a food chain.

hawks

tree shrews

caterpillars

kapok tree

What type of organism is the tree shrew?

A producer
B primary consumer
C secondary consumer
D tertiary consumer

37 The diagram shows a bacterium.

Which structure is used in genetic engineering?

D C

38 Penicillin is made in a fermenter by growing organisms.

Which type of organism is used in the production of penicillin?

A bacterium
B fungus
C protoctist
D virus

© UCLES 2019 0610/23/O/N/19 [Turn over

 16

39 What are the possible effects of deforestation?

decrease in atmospheric
loss of soil flooding
carbon dioxide

A yes yes no
B yes no yes
C no yes no
D no no yes

40 The bloodworm is an organism that is found in heavily polluted water.

The diagram shows where raw sewage flows into a river.

Where would there be fewest bloodworms?

input of raw
sewage

C D
B
direction
of flow

Permission to reproduce items where third-party owned material protected by copyright is included has been sought and cleared where possible. Every
reasonable effort has been made by the publisher (UCLES) to trace copyright holders, but if any items requiring clearance have unwittingly been included, the
publisher will be pleased to make amends at the earliest possible opportunity.

To avoid the issue of disclosure of answer-related information to candidates, all copyright acknowledgements are reproduced online in the Cambridge
Assessment International Education Copyright Acknowledgements Booklet. This is produced for each series of examinations and is freely available to download
at www.cambridgeinternational.org after the live examination series.

Cambridge Assessment International Education is part of the Cambridge Assessment Group. Cambridge Assessment is the brand name of the University of
Cambridge Local Examinations Syndicate (UCLES), which itself is a department of the University of Cambridge.

© UCLES 2019 0610/23/O/N/19

 Cambridge IGCSE™

BIOLOGY 0610/23
Paper 2 Multiple Choice (Extended) October/November 2020
45 minutes

You must answer on the multiple choice answer sheet.

*5736740124*

You will need: Multiple choice answer sheet

Soft clean eraser
Soft pencil (type B or HB is recommended)

INSTRUCTIONS
 There are forty questions on this paper. Answer all questions.
 For each question there are four possible answers A, B, C and D. Choose the one you consider correct
and record your choice in soft pencil on the multiple choice answer sheet.
 Follow the instructions on the multiple choice answer sheet.
 Write in soft pencil.
 Write your name, centre number and candidate number on the multiple choice answer sheet in the
spaces provided unless this has been done for you.
 Do not use correction fluid.
 Do not write on any bar codes.
 You may use a calculator.

INFORMATION
 The total mark for this paper is 40.
 Each correct answer will score one mark. A mark will not be deducted for a wrong answer.
 Any rough working should be done on this question paper.

This document has 16 pages. Blank pages are indicated.

IB20 11_0610_23/4RP
© UCLES 2020 [Turn over
 2

1 The diagram shows some of the processes carried out by living organisms.

carbon dioxide
in the atmosphere
X

Y
light energy
green
chicken
plant X

Y Y

waste waste
products products

Which two characteristics of living organisms are represented by arrows X and Y?

A excretion and sensitivity

B nutrition and excretion
C respiration and growth
D sensitivity and reproduction

2 What are features of the leaves of a plant that is a dicotyledon?

broad leaves parallel veins

A key
B = yes
C = no
D

© UCLES 2020 0610/23/O/N/20

 3

3 The photomicrograph shows a cell from a type of aquatic plant.

R Q P

Which parts labelled on the photomicrograph indicate that this is a plant cell?

A P and R B P and S C Q and R D Q and S

4 The diagram shows an image of a chloroplast. The image is 5 cm long.

The actual length of the chloroplast is 5 m.

What is the magnification of the image?

A 10 B 1000 C 10 000 D 100 000

5 What are features of osmosis?

requires a partially
diffusion is
requires cell walls permeable
involved
membrane

A key
B = yes
C = no
D

© UCLES 2020 0610/23/O/N/20 [Turn over

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6 The diagram shows apparatus which can be used to demonstrate osmosis.

1 2
glass tube

liquid
level

very concentrated concentrated

water
sucrose solution sucrose solution

partially
permeable membrane

After one hour, what would happen to the liquid levels in the glass tubes?

liquid level in liquid level in

tube 1 tube 2

A falls falls
B falls rises
C rises falls
D rises rises

7 Which substances are made by linking together glucose molecules only?

A cellulose, glycogen and starch

B fats, cellulose and proteins
C proteins, oils and glycogen
D starch, fats and oils

8 When bases pair up in the formation of DNA, what is one of the pairings?

A G with A B G with C C G with G D G with T

© UCLES 2020 0610/23/O/N/20

 5

9 The graph shows the effect of pH on the rate of reaction of an enzyme.

rate of
reaction

3 4 5 6 7 8 9
pH

What does the graph show?

A The enzyme is destroyed at pH 9.

B The enzyme works best at pH 6.
C The rate of reaction halves as the pH changes from pH 5 to pH 7.
D The rate of reaction is the same at pH 5 and pH 8.5.

10 The graph shows how enzyme activity is affected by temperature.

rate of
reaction

0 20 40 60
temperature / °C

How can the change in activity between 40 C and 55 C be explained?

A Heat has killed the enzyme.

B The enzyme has been used up.
C The reactants are moving faster.
D The substrate is less likely to fit into the active site.

© UCLES 2020 0610/23/O/N/20 [Turn over

 6

11 The graph shows how the rate of photosynthesis of a plant changes with light intensity, at three
different carbon dioxide concentrations. In each case the temperature is 15 C.

0.10% carbon dioxide

X
rate of 0.04% carbon dioxide
photosynthesis
0.02% carbon dioxide

light intensity

What is the limiting factor for the rate of photosynthesis at point X on the graph?

A carbon dioxide concentration

B light intensity
C surface area of the plant
D temperature

12 The diagram shows part of a leaf.

What is layer X?

A lower epidermis
B palisade mesophyll
C spongy mesophyll
D vascular bundle

© UCLES 2020 0610/23/O/N/20

 7

13 Which stage of nutrition takes place when food molecules become part of a body cell?

A absorption
B assimilation
C digestion
D ingestion

14 The diagram shows part of the alimentary canal and associated organs.

Which labelled part stores bile?

C B

15 In which order does water pass through these structures in a plant?

A mesophyll  root hair  xylem

B mesophyll  xylem  root hair

C root hair  mesophyll  xylem

D root hair  xylem  mesophyll

16 A decrease in which factor normally causes the transpiration rate to increase?

A humidity
B light intensity
C number of stomata
D temperature

17 In a mammal, what ensures the blood flows one-way round the circulatory system?

A brain
B capillaries
C lungs
D valves

© UCLES 2020 0610/23/O/N/20 [Turn over

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18 Which row correctly identifies the blood vessels?

largest internal thickest muscular transports blood

space (lumen) wall towards the heart

A pulmonary artery capillary pulmonary vein

B pulmonary artery pulmonary vein capillary
C pulmonary vein capillary pulmonary artery
D pulmonary vein pulmonary artery pulmonary vein

19 A baby acquires protection from pathogens from its mother’s breast milk.

What is this protection called?

A active immunity
B immunisation
C vaccination
D passive immunity

20 The diagram shows some of the structures in a human lung.

Where is the carbon dioxide concentration highest?

from pulmonary artery

C

to pulmonary vein

© UCLES 2020 0610/23/O/N/20

 9

21 What is produced by anaerobic respiration in yeast?

A alcohol, carbon dioxide and water

B alcohol and carbon dioxide only
C carbon dioxide and lactic acid
D lactic acid only

22 What happens as a result of deamination?

A Amino acids are converted to proteins.

B Glycogen is stored.
C Starch is produced.
D Urea is produced.

23 Sensory neurones conduct impulses from

A the brain and spinal cord to muscles.

B one sense organ to another sense organ.
C sense organs to the brain and spinal cord.
D muscles to sense organs.

24 What is a function of the cornea?

A carries impulses to the brain

B contains light-sensitive receptors
C controls how much light enters the eye
D refracts light

© UCLES 2020 0610/23/O/N/20 [Turn over

 10

25 The diagram shows some blood vessels near the surface of the skin.

skin surface

direction of
blood flow

X Y Z

If vasodilation occurs at X, what happens to the blood flow at Y and Z?

Y Z

A decreases decreases
B decreases stays constant
C increases increases
D increases stays constant

26 Which substances can be misused to improve athletic performance?

1 alcohol
2 anabolic steroids
3 testosterone

A 1, 2 and 3 B 1 and 2 only C 2 only D 2 and 3 only

© UCLES 2020 0610/23/O/N/20

 11

27 Scientists investigated the amount of genetic variation found within different crop plants. They
grew large numbers of each crop and measured the genetic variation within the species of crop.
The results are shown in the table.

percentage
crop genetic
variation

banana 0
pea 65
carrot 54

Which crop or crops have been produced by sexual reproduction?

A banana only
B banana, pea and carrot
C pea only
D pea and carrot only

28 Which organ secretes progesterone?

A ovary
B pancreas
C salivary gland
D testis

29 Which statement explains why the hormone FSH is used in fertility treatment?

A It causes the formation of a zygote during in vitro fertilisation (IVF).

B It stimulates ovulation for artificial insemination (AI).
C It stimulates the production of large numbers of eggs for use in in vitro fertilisation (IVF).
D It is used to maintain the uterus wall ready for artificial insemination (AI).

30 Which substance is coded for by a length of DNA?

A base
B glucose
C glycerol
D lipase

© UCLES 2020 0610/23/O/N/20 [Turn over

 12

31 Some features of cell division are listed.

1 chromosome number is maintained

2 haploid cells are produced
3 new cells are genetically different
4 results in variation

Which features are involved in meiosis?

A 1, 2 and 3 only
B 1, 2 and 4 only
C 2, 3 and 4 only
D 2 and 3 only

32 Which statement about the inheritance of red-green colour blindness is correct?

A The gene for red-green colour blindness is located on the X chromosome.

B Females are more likely to have red-green colour blindness than males.
C The allele for red-green colour blindness is the dominant allele.
D The gene for red-green colour blindness is located on the Y chromosome.

33 A couple are both heterozygous for the sickle-cell allele.

What is the probability that their first child will have sickle-cell anaemia?

A 25% B 33% C 50% D 75%

34 How does artificial selection differ from natural selection?

A Artificial selection changes the characteristics of living things.

B Artificial selection is based on genetic variation.
C Artificial selection does not involve competition for resources.
D Artificial selection occurs over many generations.

© UCLES 2020 0610/23/O/N/20

 13

35 The diagram shows part of the nitrogen cycle.

Which letter represents denitrification?

atmospheric
nitrogen
D ammonia

nitrites nitrites A

nitrates

nitrates plants
decay

C organic feeding
nitrogen
compounds
B animals

36 A few yeast cells were placed in a container of nutrient solution.

The graph shows how their population size changed over time.

population 4
size 2

time

Which row shows when the reproduction rate was greater than the death rate for the numbered
phases on the graph?

reproduction rate greater than death rate

1 2 3 4

A key
B = yes
C = no
D

© UCLES 2020 0610/23/O/N/20 [Turn over

 14

37 The diagram shows a fermenter used to produce penicillin.

What is the function of part X?

A allow microorganisms to enter the fermenter

B maintain an even temperature inside the fermenter
C monitor the temperature inside the fermenter
D sterilise the contents of the fermenter

38 Bacteria are used to make insulin.

This happens in several stages.

1 bacteria synthesise insulin in fermenters

2 the insulin gene is inserted into a bacterial plasmid
3 removal of the insulin gene from a human chromosome
4 a section of a plasmid is removed

In which order do these stages occur?

A 1324

B 1432

C 4231

D 4321

© UCLES 2020 0610/23/O/N/20

 15

39 The table shows some of the processes that occur during eutrophication.

Which row shows the correct increase or decrease of each process?

nitrate ion oxygen

light availability rate of respiration
availability in availability in
in the water by decomposers
the water the water

A increases decreases decreases increases

B increases decreases increases decreases
C decreases increases increases increases
D decreases increases decreases decreases

40 The graph shows the effect of fishing on fish stocks over 20 years. In year 11, a fishing quota was
introduced followed by a total ban on fishing in year 16.

key
fish stocks
mass fish caught
of fish

1 6 11 16
year

What effects did these conservation measures have on the fish population?

A The fish population became extinct.

B The fish population started increasing immediately after the fishing quota was introduced.
C The fish population started increasing only after a total ban on fishing was introduced.
D There was no effect on the fish population.

© UCLES 2020 0610/23/O/N/20

 Cambridge IGCSE™

BIOLOGY 0610/23
Paper 2 Multiple Choice (Extended) October/November 2021
45 minutes

You must answer on the multiple choice answer sheet.

*1269215875*

You will need: Multiple choice answer sheet

Soft clean eraser
Soft pencil (type B or HB is recommended)

INSTRUCTIONS
 There are forty questions on this paper. Answer all questions.
 For each question there are four possible answers A, B, C and D. Choose the one you consider correct
and record your choice in soft pencil on the multiple choice answer sheet.
 Follow the instructions on the multiple choice answer sheet.
 Write in soft pencil.
 Write your name, centre number and candidate number on the multiple choice answer sheet in the
spaces provided unless this has been done for you.
 Do not use correction fluid.
 Do not write on any bar codes.
 You may use a calculator.

INFORMATION
 The total mark for this paper is 40.
 Each correct answer will score one mark.
 Any rough working should be done on this question paper.

This document has 16 pages.

IB21 11_0610_23/6RP
© UCLES 2021 [Turn over
 2

1 An Amoeba is a single-celled organism.

The diagram shows an Amoeba engulfing a food particle.

Amoeba

food particle

Which characteristics of living organisms are shown?

A excretion, movement and nutrition

B excretion, nutrition and sensitivity
C movement, nutrition and sensitivity
D movement, reproduction and sensitivity

2 Two animals have an identical sequence of amino acids in one of the proteins found in their cells.

What does this indicate about these animals?

A They have been eating the same types of food.

B They have not been exposed to substances that cause mutation.
C They must be members of the same genus.
D They share an ancestor.

3 The diagram shows two guard cells.

Which label is correct?

A cell membrane

B cell wall

C vacuole

D cytoplasm

4 The length of a mitochondrion in a photomicrograph is 15 mm.

The actual length of the mitochondrion is 3 m.

What is the magnification of the photomicrograph?

A 5 B 45 C 5000 D 45 000

© UCLES 2021 0610/23/O/N/21

 3

5 The diagram shows some cells.

cilia

cytoplasm

nucleus

Where are these cells found?

A alimentary canal
B blood
C bronchus
D plant roots

6 In which diagram would oxygen diffuse into the cell?

A B

high oxygen low oxygen high oxygen high oxygen

concentration concentration concentration concentration
in the cell outside of the cell in the cell outside of the cell

cell membrane cell membrane

C D

low oxygen low oxygen low oxygen high oxygen

concentration concentration concentration concentration
in the cell outside of the cell in the cell outside of the cell

cell membrane cell membrane

7 Which statement about the role of the pressure of water in supporting plants is correct?

A The pressure of water inside the cells presses inwards on the cell wall.
B The pressure of water outside the cells presses inwards on the cell wall.
C The pressure of water inside the cells presses outwards on the cell wall.
D The pressure of water outside the cells presses outwards on the cell wall.

© UCLES 2021 0610/23/O/N/21 [Turn over

 4

8 The bases on one of the strands of a DNA molecule have the sequence shown.

A-A-T-C-T-G

What is the corresponding sequence of bases on the other strand?

A A-A-T-C-T-G
B C-C-G-A-G-T
C G-G-C-T-C-A
D T-T-A-G-A-C

9 In a photosynthesis experiment, a plant is left in bright sunlight for several hours. A leaf is then
removed from the plant and tested for starch, using iodine solution.

The diagram shows the leaf from the plant that was used in the experiment.

white area

green area

Which diagram shows the result of the experiment?

A B C D
key
iodine solution
turns blue-black
iodine solution
stays brown

© UCLES 2021 0610/23/O/N/21

 5

10 An experiment was carried out to investigate the effect of pH on enzyme action. The graph shows
the results.

y-axis

x-axis

What are the labels for the x-axis and the y-axis?

x-axis y-axis

A pH rate of reaction
B pH time
C rate of reaction pH
D time pH

11 Four test-tubes were set up as shown in the diagram.

In which test-tube is the starch digested most quickly?

A B C D

water-bath water-bath
at 15 °C at 35 °C

starch solution starch solution

and amylase and amylase

starch solution starch solution

and boiled amylase and boiled amylase

© UCLES 2021 0610/23/O/N/21 [Turn over

 6

12 Two similar leaves are set up in test-tubes as shown. One is exposed to light, while the other is
kept in the dark.

green leaf
green leaf

black paper

orange
hydrogencarbonate
indicator solution

After a few hours, which colour would the hydrogencarbonate indicator solution be in each
test-tube?

light dark

A colourless blue-black
B purple yellow
C red blue
D yellow purple

© UCLES 2021 0610/23/O/N/21

 7

13 The diagram shows part of a leaf cross-section.

Which cells can carry out photosynthesis?

A 1, 2 and 3 B 2, 3 and 4 C 2, 4 and 5 D 1, 3 and 5

14 Which part of the alimentary canal produces an enzyme that digests proteins?

A C

© UCLES 2021 0610/23/O/N/21 [Turn over

 8

15 The diagram shows a large food molecule changing into smaller molecules.

process X

What is process X?

A absorption
B chewing
C digestion
D secretion

16 How is the structure of root hair cells related to their function?

A They have chloroplasts for photosynthesis.

B Their cell wall is partially permeable to absorb water by osmosis.
C They have a large surface area to increase the rate of mineral ion uptake.
D Both the cell wall and cell membrane control the active uptake of mineral ions.

17 In plants, how are amino acids moved between sources and sinks?

A by translocation through xylem vessels

B by transpiration through phloem tissues
C by translocation through phloem tissues
D by transpiration through xylem vessels

18 Which component of blood produces antibodies?

A lymphocytes
B phagocytes
C plasma
D red blood cells

© UCLES 2021 0610/23/O/N/21

 9

19 The diagram shows the external structure of the human heart.

Which label identifies a coronary artery?

20 Which row shows what happens at the start of inspiration?

external internal
volume air pressure
intercostal intercostal diaphragm
of thorax in thorax
muscles muscles contracts
increases increases
contract contract

A key
B = yes
C = no
D

© UCLES 2021 0610/23/O/N/21 [Turn over

 10

21 Some features that help to defend the body against pathogens are listed.

1 mucus
2 skin
3 stomach acid
4 phagocytosis

Which features can prevent pathogens entering body tissues?

A 1, 2, 3 and 4
B 1, 2 and 3 only
C 2 and 3 only
D 4 only

22 The diagram shows the human gas exchange system.

Which row shows the correct labels?

part of the gas exchange system

1 2 3 4

A trachea larynx bronchus diaphragm

B larynx trachea bronchus diaphragm
C trachea larynx diaphragm bronchus
D larynx trachea diaphragm bronchus

© UCLES 2021 0610/23/O/N/21

 11

23 What is the equation for anaerobic respiration in yeast?

A C6H12O6 + 6O2  6CO2 + 6H2O

B C6H12O6  2C3H6O3

C C6H12O6  2C2H5OH + 2CO2

D 6CO2 + 6H2O  C6H12O6 + 6O2

24 The diagram shows a kidney tubule.

In which part of the tubule is the glucose concentration highest?

position of
glomerulus

D
A

to ureter

25 What happens to the muscles in the iris when a person moves from a brightly lit room to a dimly
lit room?

A The circular muscles and the radial muscles relax.

B The circular muscles contract and the radial muscles relax.
C The circular muscles and the radial muscles contract.
D The circular muscles relax and the radial muscles contract.

© UCLES 2021 0610/23/O/N/21 [Turn over

 12

26 What happens when someone has a low blood glucose concentration?

A Insulin is released from the pancreas.

B Glycogen is released from the pancreas.
C Glucagon is released from the liver.
D Glucose is released from the liver.

27 How can the development of antibiotic resistance in bacteria be reduced?

A treating every disease with antibiotics

B treating infections caused by a virus with antibiotics
C using antibiotics only when essential
D using antibiotics regularly to prevent disease

28 A seed is placed and grown on a rotating disc, as shown.

seed pinned to the

constantly rotating disc

Which diagram shows the appearance of the seedling shoot after seven days?

A B C D

29 Which statement describes a structural adaptation of wind-pollinated flowers?

A They have long filaments so that the anthers hang outside of the flower.
B They have round, sticky sepals to trap pollen grains.
C Their large petals protect the stigma.
D Their stamens are feathery so there is a large surface area.

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30 What are likely consequences of HIV infection?

1 decreased lymphocyte numbers

2 reduced active immunity
3 reduced passive immunity

A 1, 2 and 3 B 1 and 2 only C 1 and 3 only D 2 and 3 only

31 Which row is correct for the type of cell?

sets of
type of cell nucleus
chromosomes

A body diploid two

B gamete diploid one
C gamete haploid two
D body haploid one

32 Which structures in bacterial cells synthesise proteins?

A cell wall
B chloroplasts
C nucleus
D ribosomes

33 A man with blood group AB and a woman with blood group O have a child.

What are the correct percentages of the possible blood groups for this child?

A 50% A and 50% B

B 50% AB and 50% O
C 25% A, 25% B and 50% O
D 25% AB, 25% A, 25% B and 25% O

34 Which statement about a person who is heterozygous for the sickle-cell allele is correct?

A They are not resistant to malaria and their genotype is HbAHbS.

B They are not resistant to malaria and their genotype is HbSHbS.
C They are resistant to malaria and their genotype is HbAHbS.
D They are resistant to malaria and their genotype is HbSHbS.

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35 A species of insect usually has pale-coloured wings. This helps to camouflage them on
pale-coloured tree trunks. A few of the insects in this species have darker coloured wings.

After a number of years the tree trunks become darker in colour due to environmental changes.
The insects with dark-coloured wings become more common than insects with pale-coloured
wings in this species.

Which process causes this change in the proportion of insects with dark-coloured wings?

A biotechnology
B conservation
C natural selection
D selective breeding

36 The diagram shows part of the nitrogen cycle.

Which letter represents denitrification?

nitrogen
gas in air
B
A
animals plants

D faeces
nitrate ions
C in soil
ammonium
ions in soil

37 Reasons why bacteria might be used in biotechnology and genetic engineering are listed.

1 All bacteria are harmless organisms.

2 Bacteria contain plasmids.
3 Bacteria share the same genetic code as other organisms.
4 There is a lack of ethical concerns about using bacteria.

Which reasons make bacteria useful in biotechnology and genetic engineering?

A 1, 2 and 3 B 2, 3 and 4 C 1 and 4 D 2 and 3 only

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38 Bacteria can be genetically engineered to produce human proteins, such as human insulin.

Which enzyme is used to join the human gene and the bacterial plasmid together to create a
recombinant plasmid?

A lipase
B recombinant enzyme
C DNA ligase
D restriction enzyme

39 The bar chart shows the tolerance of some river organisms to different levels of pH.

trout
bass
perch
frogs
salamanders
clams
crayfish
snails
mayflies
6.5 6.0 5.5 5.0 4.5 4.0
pH

Which organisms would be most affected if the pH of a river decreased from pH 6.0 to pH 5.5?

A crayfish and mayflies

B frogs and perch
C snails and clams
D trout and salamanders

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40 What is meant by a sustainable resource?

A a resource that is produced by non-intensive farming and is rarely used

B a resource that is removed from a habitat without changing the environment
C a resource that does not pollute the environment
D a resource that is produced as rapidly as it is removed from the environment

Permission to reproduce items where third-party owned material protected by copyright is included has been sought and cleared where possible. Every
reasonable effort has been made by the publisher (UCLES) to trace copyright holders, but if any items requiring clearance have unwittingly been included, the
publisher will be pleased to make amends at the earliest possible opportunity.

To avoid the issue of disclosure of answer-related information to candidates, all copyright acknowledgements are reproduced online in the Cambridge
Assessment International Education Copyright Acknowledgements Booklet. This is produced for each series of examinations and is freely available to download
at www.cambridgeinternational.org after the live examination series.

Cambridge Assessment International Education is part of the Cambridge Assessment Group. Cambridge Assessment is the brand name of the University of
Cambridge Local Examinations Syndicate (UCLES), which itself is a department of the University of Cambridge.

© UCLES 2021 0610/23/O/N/21

 Cambridge IGCSE™

BIOLOGY 0610/23
Paper 2 Multiple Choice (Extended) October/November 2022
45 minutes

You must answer on the multiple choice answer sheet.

*3591968192*

You will need: Multiple choice answer sheet

Soft clean eraser
Soft pencil (type B or HB is recommended)

INSTRUCTIONS
 There are forty questions on this paper. Answer all questions.
 For each question there are four possible answers A, B, C and D. Choose the one you consider correct
and record your choice in soft pencil on the multiple choice answer sheet.
 Follow the instructions on the multiple choice answer sheet.
 Write in soft pencil.
 Write your name, centre number and candidate number on the multiple choice answer sheet in the
spaces provided unless this has been done for you.
 Do not use correction fluid.
 Do not write on any bar codes.
 You may use a calculator.

INFORMATION
 The total mark for this paper is 40.
 Each correct answer will score one mark.
 Any rough working should be done on this question paper.

This document has 16 pages. Any blank pages are indicated.

IB22 11_0610_23/4RP
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1 Which process provides an organism with the raw materials needed for tissue repair?

A excretion
B growth
C nutrition
D respiration

2 Which name is given to a group of individuals that can reproduce to produce fertile offspring?

A a genus
B a kingdom
C a species
D an organ system

3 Root hair cells are found on plant roots.

Which feature is present in a root hair cell but not in a sperm cell?

A cell membrane
B cell wall
C chloroplasts
D cytoplasm

4 What is an example of a tissue?

A a chloroplast
B the palisade mesophyll
C a neurone
D the pancreas

5 Some examples of substances moving across membranes are listed.

1 glucose molecules into the epithelium that lines the small intestine
2 nitrate ions from a dilute solution in soil into a more concentrated solution in root hair
cells
3 water molecules from mesophyll cells into the air spaces of a leaf

For which examples must oxygen be present?

A 1, 2 and 3 B 1 and 2 only C 1 and 3 only D 2 and 3 only

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6 In which diagram would most oxygen molecules diffuse across the membrane per minute?

A B
30 °C 70 °C 30 °C 70 °C

key
membrane
C D oxygen molecules
30 °C 70 °C 30 °C 70 °C

7 The list shows some statements about enzymes.

1 They all contain the element nitrogen.

2 They are proteins.
3 They can be denatured by cold temperatures.
4 Their specificity is due to the complementary shapes of the active site and the
substrate.

Which statements are correct?

A 1, 2 and 3 B 1, 2 and 4 C 2 and 4 only D 3 and 4

8 Which statement about the structure of DNA is correct?

A DNA contains six types of base.

B DNA contains three strands coiled to form a helix.
C DNA is made of a chain of amino acids.
D DNA has two strands with cross-links between pairs of bases.

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9 A doctor tested the urine of four patients for both glucose and protein. The colours of the urine
samples after testing are shown in the table.

Which patient’s urine contained both protein and glucose?

colour after colour after

testing with testing with
biuret solution Benedict’s solution

A blue brick red

B blue blue
C purple brick red
D purple blue

10 The equation shows the digestion of protein to amino acids.

protease
protein amino acids

In the equation, what is protease?

A a catalyst

B a product
C a solvent
D a substrate

11 The graph shows the effect of increasing light intensity on the rate of photosynthesis.

rate of
photosynthesis X

light intensity

What are the limiting factors at X and Y?

X Y

A carbon dioxide concentration carbon dioxide concentration

B carbon dioxide concentration light intensity
C light intensity carbon dioxide concentration
D light intensity light intensity

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12 The substances listed are found in the leaf of a plant.

Which substance is obtained from the soil?

A carbon dioxide
B chlorophyll
C glucose
D mineral ions

13 The cholera bacterium produces toxins that cause chloride ions to be secreted into the small
intestine.

What is the immediate effect of this on the water potential of blood in the intestinal capillaries, and
on the water potential of the contents of the small intestine?

water potential
blood in contents of
capillaries small intestine

A lowered lowered
B lowered raised
C raised lowered
D raised raised

14 The graph shows the concentration of maltose in different parts of the alimentary canal.

maltose
concentration

mouth stomach small intestine

distance through the alimentary canal

What causes the change in concentration at X?

A absorption of maltose
B action of amylase
C action of maltase
D assimilation of maltose

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15 The diagram shows a bean seedling soon after it has germinated.

Where is most water absorbed?

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16 Scientists investigate the movement of substances in a plant.

They cut a ring of tissue from the stem.

Removing the tissue removes some of the transport vessels found around the edge of the stem.

A few days later they notice swelling above the area where the tissue has been removed.

leaves

tissue
removed time swelling

roots

What causes the swelling?

A Phloem vessels have been removed and sucrose cannot move to the sink.
B Phloem vessels have been removed and sucrose cannot move to the source.
C Xylem vessels have been removed and minerals cannot move to the sink.
D Xylem vessels have been removed and minerals cannot move to the source.

17 The diagram shows the outside of a human heart.

Which structure is a coronary artery?

A B
C

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18 The diagrams represent blood flow in the circulatory systems of fish and humans.

fish circulation human circulation

gills
body
4
1 2 lungs
heart 5
6
heart
3 body

In the fish circulation and the human circulation, where is the oxygen concentration highest?

fish human
circulation circulation

A 1 4
B 1 5
C 2 4
D 3 6

19 Campylobacter is a bacterium that can cause food poisoning.

Which word describes Campylobacter?

A antibody
B disease
C pathogen
D symptom

20 What is the approximate percentage of oxygen in expired air?

A 0.04% B 4% C 16% D 21%

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21 Which actions use energy released from respiration?

1 muscle contraction
2 protein synthesis
3 cell division
4 transmitting nerve impulses

A 1, 2, 3 and 4
B 1, 2 and 4 only
C 2 and 3 only
D 3 and 4 only

22 What is the word equation for anaerobic respiration in muscle cells?

A glucose + oxygen  lactic acid

B glucose  carbon dioxide

C glucose + carbon dioxide  alcohol

D glucose  lactic acid

23 Which statement about the formation of urea is correct?

A Urea is formed in the kidneys from excess amino acids.

B Urea is formed in the liver from excess amino acids.
C Urea is formed in the kidneys from excess fatty acids.
D Urea is formed in the liver from excess fatty acids.

24 What is a response to a low concentration of glucose in the blood?

A Glucagon will cause the body to convert glucose into glycogen.

B Glucagon will cause the body to convert glycogen into glucose.
C Insulin will cause the body to convert glucose into glycogen.
D Insulin will cause the body to convert glycogen into glucose.

25 Which endocrine gland secretes insulin?

A adrenal
B ovary
C pancreas
D testis

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26 Which factors affect the growth of plants?

A gravity and light only

B gravity, light and temperature
C gravity and temperature only
D light and temperature only

27 The table shows the recommended daily amounts (RDA) of some nutrients for a person with
special dietary requirements, and their actual intake of those nutrients.

dietary RDA for

actual intake
component this person

carbohydrate / g 260 265

protein / g 44 41
fat / g 33 32
vitamin C / mg 60 5
vitamin D / g 10 11
fibre / g 26 27
iron / mg 15 15
calcium / mg 700 710

What would the person be at risk of developing if they continued with the same daily intake of
these nutrients?

A constipation
B coronary heart disease
C obesity
D scurvy

28 What are advantages of using sexual reproduction to produce crop plants?

1 It produces genetic variation to help breed new varieties of crop plant.

2 It ensures that crops have the identical characteristics.
3 It quickly produces many identical copies of a plant.

A 1, 2 and 3 B 1 and 2 only C 1 only D 2 and 3 only

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29 Where is the hormone progesterone produced?

1 ovaries
2 placenta
3 uterus

A 1 only B 1 and 2 only C 2 and 3 only D 1, 2 and 3

30 Which row correctly describes mitosis?

number of
new cells are duplication of
chromosomes in a
genetically identical chromosomes
daughter cell compared
to the parent cell occurs
to the parent cell

A no before mitosis same

B no during mitosis halved
C yes before mitosis same
D yes during mitosis halved

31 The diagram shows the flow of energy through a food chain.

1
5

2 4 6 7

Which row correctly labels this energy flow diagram?

chemical
chemical chemical energy
energy loss energy in
energy in energy in loss by
by excretion tertiary
producers decomposers respiration
consumers

A 2 8 5 3 7
B 1 7 5 3 6
C 2 8 3 5 7
D 1 7 3 5 6

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32 A man and a woman have four children. The diagram shows the blood groups of the children.

father mother

child 1 child 2 child 3 child 4

group A group AB group O group O

What are the possible genotypes of the father and mother?

A IAIA and IBIo

B IAIB and IoIo
C IAIo and IBIB
D IAIo and IBIo

33 How do the leaves of hydrophytes differ from those of xerophytes?

A more hairs on the surface of the leaves

B smaller total surface area
C stomata on the undersides of the leaves
D thinner cuticle

34 Broccoli and cauliflower are crop plants that have been produced from a common wild plant.

Which process would be used to produce the broccoli and cauliflower plants from wild plants?

A artificial selection
B competition
C evolution
D natural selection

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35 The diagram shows part of the nitrogen cycle.

nitrogen in the
atmosphere

bacterium X

nitrates in soil

Which process in the cycle is performed by bacterium X?

A decomposition
B nitrification
C nitrogen fixation
D denitrification

36 The graph shows changes in the population size of a microorganism growing in a fermenter.

What is the exponential phase?

A B C D

population
size

time

37 Bacteria are useful in genetic engineering because they possess plasmids.

Which statement describes the importance of a plasmid?

A It is a circle of DNA and human genes can be inserted into it.

B It is the nucleus of the bacterium and human genes can be inserted into it.
C It can be destroyed and replaced with human insulin.
D It is a circle of DNA and human insulin can be inserted into it.

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38 Which statement is correct?

A DNA ligase is used to cut DNA.

B DNA ligase is used to make proteins.
C Restriction enzymes are used to cut DNA.
D Restriction enzymes are used to make proteins.

39 What can reduce the occurrence of famine?

A increasing population size

B long periods of drought
C poverty
D equal distribution of food

40 What is a consequence of deforestation?

A flooding due to reduced transpiration by trees

B increased carbon dioxide concentration in the atmosphere due to increased photosynthesis
C reduced carbon dioxide concentration in the atmosphere due to increased decomposition of
dead trees
D reduced oxygen concentration in the atmosphere due to reduced respiration of trees

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