10 (a) A farmer keeps ponies. The ponies show variation in height. The farmer sells the smaller ponies for more money than the larger ponies. (i) Name the type of variation shown by differences in height of the ponies. … [1] (ii) Complete the sentences to describe the method the farmer uses to increase the number of smaller ponies on the farm. The farmer selects the ponies with the desirable feature. These ponies are then … . The … offspring are then selected and used for … . This process is then … over many generations. [4] (iii) State the name of the process the farmer uses. … [1] (b) The inheritance of sex in ponies is the same as in humans. (i) Complete Table 10.1 to show the inheritance of sex. Table 10.1 male sex chromosomes X … female sex chromosomes X XX XY … XX XY [1] (ii) State the ratio of male to female offspring shown in Table 10.1. … [1] (c) Chromosomes contain genes. Define the term gene. … … [2] [Total: 10]

10(a)(i) continuous ; 1 10(a)(ii) crossed / bred / AW ; smallest ; breeding ; repeated ; 4 10(a)(iii) selective breeding ; 1 10(b)(i) X Y X XX XY X XX XY ; 1 10(b)(ii) 1:1 ; 1 10(c) length of DNA ; that codes for a protein ; 2

4 (a) Antibiotics are drugs that are used to kill bacteria. A scientist investigates antibiotic resistance in bacteria. The scientist uses four different antibiotics discs A, B, C and D. The results are shown in Fig. 4.1. The white areas show where no bacteria have grown. The dark areas show where bacteria have grown. A B C D no bacterial growth bacterial growth Fig. 4.1 (i) Identify the antibiotic that is most effective against the bacteria. … [1] (ii) Identify the antibiotic that the bacteria are most resistant to. … [1] (b) The development of antibiotic resistance is an example of evolution by natural selection. (i) Complete the sentences to describe how strains of bacteria with antibiotic resistance develop. A mutation occurs which causes a change in the … . This mutation causes some bacteria to be resistant to antibiotics. Antibiotics kill non-resistant bacteria. Resistant bacteria survive and … . The … for resistance is passed on to their offspring. Eventually all the population of bacteria will be resistant to antibiotics. [3] (ii) Describe one way natural selection is different from artificial selection. … … [1] (c) Bacteria reproduce by a type of asexual reproduction. State one advantage and one disadvantage of asexual reproduction. advantage … … disadvantage … … [2] [Total: 8]

4(a)(i) D ; 1 4(a)(ii) C ; 1 4(b)(i) chromosome / gene ; reproduce / AW ; allele ; 3 4(b)(ii) traits / characteristics, are selected by humans (in artificial selection) / traits are selected by the environment in natural selection ; traits / characteristics, are usually chosen for economic reasons (in artificial selection) / traits are beneficial for survival in natural selection ; faster results (from artificial selection) / ORA ; (artificial selection only) takes place in selected individuals / natural selection takes place in whole populations ; (artificial selection) does not lead to evolution / ORA ; (artificial selection) results in decreased (genetic) variation / diversity / ORA ; (artificial selection) leads to increased likelihood of inherited / genetic disease ; AVP ; max1 4(c) advantages: no mates required / rapid / AVP ; disadvantages no (genetic) diversity / no evolution / extinction more likely ; 2

4 (a) Complete the definition of the term ecosystem. An ecosystem is defined as a unit containing all of the … and their environment, … together, in a given area. [2] (b) Fig. 4.1 is part of a food web. owl grass grasshopper mice wheat blackbird Fig. 4.1 Use Fig. 4.1 to answer the following questions. (i) State the number of trophic levels in this food web. … [1] (ii) Name the general term given to the type of organisms that occupy the first trophic level. … [1] (iii) Name the organism that feeds at the 2nd and 3rd trophic level. … [1] (iv) Explain why there are fewer numbers of organisms in the 3rd trophic level than in the 2nd trophic level. … … … … … … [3] (c) Wheat is a type of crop plant. The statements outline how artificial selection is used to improve yield of crop plants such as wheat. The yield is the amount of wheat crop produced in a given area. They are not in the correct order. Write numbers next to the statements to show the correct order. The first one has been done for you. This process is repeated over many generations. The offspring are observed and those that produce the highest yield are chosen and bred again. Eventually the entire population of wheat plants will produce high yields. Wheat plants are observed to see which produce the highest yield. 1 These wheat plants are crossed to produce offspring. [1] (d) State two ways that artificial selection is different from natural selection. 1 … 2 … [2] [Total: 11]

4(a) organisms ; interacting ; 2 4(b)(i) 4 ; 1 4(b)(ii) producers ; 1 4(b)(iii) blackbirds ; 1 4(b)(iv) any three from: energy is lost between the trophic levels ; energy lost by, respiration / movement / heat / excretion ; not all the organism, is eaten / digested ; not enough energy for larger number of organisms ; 3 4(c) 4 3 5 (1) 2 ; 1 4(d) any two from: traits / characteristics, are selected by humans (in artificial selection) / traits are selected by the environment in natural selection ; traits / characteristics, are usually chosen for economic reasons (in artificial selection) / traits are beneficial for survival (in natural selection) ; faster results (from artificial selection) / ORA ; (artificial selection only) takes place in selected individuals / natural selection takes place in whole populations ; (artificial selection) does not lead to evolution / ORA ; (artificial selection) results in decreased genetic variation / diversity / ORA ; (artificial selection) leads to increased likelihood of inherited / genetic disease ; AVP ; 2

10 (a) The blood groups of some people are recorded. Fig. 10.1 shows the results. 0 A AB B O 5 10 15 20 number of people 25 30 35 40 blood group Fig. 10.1 (i) State the total number of people who had their blood group recorded. … [1] (ii) Describe the evidence in Fig. 10.1 that shows blood group is an example of discontinuous variation. … … … … [2] (iii) Complete this sentence about discontinuous variation. Discontinuous variation is mostly caused by … alone. [1] (iv) Name one example of continuous variation in humans. … [1] (b) Blood contains four main components. The boxes on the left show the components of blood. The boxes on the right show the functions of each component. Draw lines to link each component with its function. component function plasma antibody production platelet blood clotting red blood cell transport of ions, soluble nutrients and hormones white blood cell transport of oxygen [3] (c) Describe two ways the structure of a red blood cell is adapted to its function. 1 … 2 … [2] [Total: 10]

10(a)(i) 100 ; 1 10(a)(ii) limited number of phenotypes ; no intermediates ; 2 10(a)(iii) genes ; 1 10(a)(iv) height / AVP ; 1 10(b) plasma antibody production platelets blood clotting red blood cell transport of ions, soluble nutrients and hormones white blood cell transport of oxygen ;;; 3 10(c) any two from: no nucleus ; contains haemoglobin ; biconcave shape / large surface area ; 2

Cambridge IGCSE Co-ordinated Sciences · 0654

IGCSE Co-ordinated Sciences (0654) Variation and selection past paper questions

Revise IGCSE Co-ordinated Sciences (0654) — Variation and selection with real Cambridge past-paper questions grouped by topic, each shown with its marking scheme. Working one topic at a time targets exactly the skill each question tests.

37 free questions from 2016–2021, each with its marking scheme. Open the full topical bank to filter by subtopic, paper, and year.

Variation and selection in IGCSE Co-ordinated Sciences 0654 exams, 2020–2025

Across 2020–2025, Variation and selection accounted for 57 questions worth 328 marks in Cambridge IGCSE Co-ordinated Sciences (0654) papers.

By year
Year	Questions	Marks
2020	10	63
2021	6	41
2022	9	50
2023	12	47
2024	8	56
2025	12	71

Most-tested subtopics

B17.2 Selection215 marks
B17.1 Variation172 marks

Appears in

Paper 1 · 15 qs
Paper 2 · 10 qs
Paper 3 · 17 qs
Paper 4 · 14 qs
Paper 6 · 1 q

All most-tested Co-ordinated Sciences topics

2021 Feb/Mar · Paper 3 · Q10 · 10 marks
Marking scheme
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2021 Oct/Nov · Paper 4 · Q4 · 8 marks
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2021 Oct/Nov · Paper 4 · Q4 · 11 marks
Marking scheme
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2021 Feb/Mar · Paper 4 · Q10 · 10 marks
Marking scheme
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2021 Oct/Nov · Paper 1 · Q11 · 1 mark
Marking scheme
Mark scheme — 2021 Paper 1 Q11
Answer: B
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