Skip to content
Try on iPad

Manipulating genomes: OCR A‑Level Biology A questions

Every OCR A-Level Biology A exam question on 6.1.3 Manipulating genomes, 2016–2025, with its mark scheme and examiner’s report.

Find questions1,984
Calculations

1,984 questions

  1. Q10

    June 2025 · Paper 2

    1 mark6.1.3 Manipulating genomes
    The whole paper ↗
    June 2025 Paper 2, question 10: The use of genetically modified (GM) crops in agriculture raises certain concerns. What is not a valid concern about the use of GM crops in agriculture? A Eatin

  2. Q11

    June 2025 · Paper 2

    1 mark6.1.3 Manipulating genomes
    The whole paper ↗
    June 2025 Paper 2, question 11: Which statement about DNA sequencing is not correct? A High-throughput sequencing allows DNA to be sequenced quickly. B Nucleotides are added to a growing stran

  3. Q4(d)(i)

    June 2025 · Paper 3

    4 marks6.1.3 Manipulating genomes
    The whole paper ↗
    June 2025 Paper 3, question 4(d)(i): The diagram shows an electrophoresis box. Solutions of DNA samples have been added to three of the wells in the box. Solutions containing DNA samples Negative e

  4. Q4(d)(ii)

    June 2025 · Paper 3

    2 marks6.1.3 Manipulating genomes
    The whole paper ↗
    June 2025 Paper 3, question 4(d)(ii): Electrophoresis can be used to detect disease‑causing alleles, such as the mutant HBB allele that causes sickle cell disease. Restriction enzymes are used to pr

  5. Q4(e)(i)

    June 2025 · Paper 3

    2 marks6.1.3 Manipulating genomes
    The whole paper ↗
    June 2025 Paper 3, question 4(e)(i): A scientist estimates that 40% of their plasmids join to the donor gene to form recombinant DNA. One in 2500 bacterial cells takes up a plasmid to form a transf

  6. Q4(e)(ii)

    June 2025 · Paper 3

    1 mark6.1.3 Manipulating genomes
    The whole paper ↗
    June 2025 Paper 3, question 4(e)(ii): The percentage of plasmids that are taken up by bacterial cells is known as the transformation efficiency. Suggest one factor that scientists could change to im

  7. Q6(b)

    June 2025 · Paper 3

    6 marks6.1.3 Manipulating genomes
    The whole paper ↗
    June 2025 Paper 3, question 6(b): β‑thalassemia is an inherited blood disorder in which the β‑globin chain of haemoglobin is changed or absent in a person’s red blood cells. Many different DNA m

  8. Q16(a)

    June 2024 · Paper 2

    1 mark6.1.3 Manipulating genomes
    The whole paper ↗
    June 2024 Paper 2, question 16(a): DNA profiling is used in the investigation of crime and in paternity cases. State one other use of DNA profiling. [1]

  9. Q16(b)(i)

    June 2024 · Paper 2

    1 mark6.1.3 Manipulating genomes
    The whole paper ↗
    June 2024 Paper 2, question 16(b)(i): Name the technique known as PCR. [1]

  10. Q16(b)(ii)

    June 2024 · Paper 2

    3 marks6.1.3 Manipulating genomes
    The whole paper ↗
    June 2024 Paper 2, question 16(b)(ii): Outline the process of PCR, with reference to steps X, Y and Z. X Y Z [3]

  11. Q16(b)(iii)

    June 2024 · Paper 2

    3 marks6.1.3 Manipulating genomes
    The whole paper ↗
    June 2024 Paper 2, question 16(b)(iii): Explain why a temperature of 72–75 °C is used for step Z. [3]

  12. Q16(b)(iv)

    June 2024 · Paper 2

    1 mark6.1.3 Manipulating genomes
    The whole paper ↗
    June 2024 Paper 2, question 16(b)(iv): Suggest why a PCR step is usually necessary when creating a DNA profile from a crime scene sample in particular. [1]

  13. Q16(c)(i)

    June 2024 · Paper 2

    2 marks6.1.3 Manipulating genomes
    The whole paper ↗
    June 2024 Paper 2, question 16(c)(i): Suggest why some loci have two peaks but some have only one. [2]

  14. Q16(c)(ii)

    June 2024 · Paper 2

    3 marks6.1.3 Manipulating genomes
    The whole paper ↗
    June 2024 Paper 2, question 16(c)(ii): Using the evidence in the DNA profile it was claimed that suspect S had been at the crime scene. Explain how strongly the evidence supports this claim. [3]

  15. Q18(b)(i)

    June 2024 · Paper 2

    6 marks6.1.3 Manipulating genomes
    The whole paper ↗
    June 2024 Paper 2, question 18(b)(i): Synthetic biology involves re-designing organisms for useful purposes. One such purpose could be the production of useful proteins. Proteins can be produced by

  16. Q18(b)(ii)

    June 2024 · Paper 2

    1 mark6.1.3 Manipulating genomes
    The whole paper ↗
    June 2024 Paper 2, question 18(b)(ii): Suggest why some people might be concerned about the increase of synthetic biology. [1]

  17. Q5(e)(i)

    June 2024 · Paper 3

    1 mark6.1.3 Manipulating genomes
    The whole paper ↗
    June 2024 Paper 3, question 5(e)(i): State how a plasmid containing the gene coding for insulin can be transferred into a bacterial cell. [1]

  18. Q5(e)(ii)

    June 2024 · Paper 3

    1 mark6.1.3 Manipulating genomes
    The whole paper ↗
    June 2024 Paper 3, question 5(e)(ii): Suggest how bacterial cells can be screened to check if they have taken up a recombinant plasmid. [1]

  19. Q3(a)(iii)

    June 2023 · Paper 3

    1 mark6.1.3 Manipulating genomes
    The whole paper ↗
    June 2023 Paper 3, question 3(a)(iii): Often a single company holds the patent for a GM crop plant. Suggest a potential ethical issue that may exist if one company holds the patent for a GM crop plan

  20. Q3(b)

    June 2023 · Paper 3

    3 marks6.1.3 Manipulating genomes
    The whole paper ↗
    June 2023 Paper 3, question 3(b): Humans have been selectively breeding maize as a crop plant for thousands of years, which has resulted in many different varieties of maize. Different varieties
All 57 questions on Manipulating genomes, as a list
  1. June 2025, Paper 2, Q10 (1 mark): The use of genetically modified (GM) crops in agriculture raises certain concerns. What is not a valid concern about the use of GM crops in agriculture? A Eatin
  2. June 2025, Paper 2, Q11 (1 mark): Which statement about DNA sequencing is not correct? A High-throughput sequencing allows DNA to be sequenced quickly. B Nucleotides are added to a growing stran
  3. June 2025, Paper 3, Q4(d)(i) (4 marks): The diagram shows an electrophoresis box. Solutions of DNA samples have been added to three of the wells in the box. Solutions containing DNA samples Negative e
  4. June 2025, Paper 3, Q4(d)(ii) (2 marks): Electrophoresis can be used to detect disease‑causing alleles, such as the mutant HBB allele that causes sickle cell disease. Restriction enzymes are used to pr
  5. June 2025, Paper 3, Q4(e)(i) (2 marks): A scientist estimates that 40% of their plasmids join to the donor gene to form recombinant DNA. One in 2500 bacterial cells takes up a plasmid to form a transf
  6. June 2025, Paper 3, Q4(e)(ii) (1 mark): The percentage of plasmids that are taken up by bacterial cells is known as the transformation efficiency. Suggest one factor that scientists could change to im
  7. June 2025, Paper 3, Q6(b) (6 marks): β‑thalassemia is an inherited blood disorder in which the β‑globin chain of haemoglobin is changed or absent in a person’s red blood cells. Many different DNA m
  8. June 2024, Paper 2, Q16(a) (1 mark): DNA profiling is used in the investigation of crime and in paternity cases. State one other use of DNA profiling. [1]
  9. June 2024, Paper 2, Q16(b)(i) (1 mark): Name the technique known as PCR. [1]
  10. June 2024, Paper 2, Q16(b)(ii) (3 marks): Outline the process of PCR, with reference to steps X, Y and Z. X Y Z [3]
  11. June 2024, Paper 2, Q16(b)(iii) (3 marks): Explain why a temperature of 72–75 °C is used for step Z. [3]
  12. June 2024, Paper 2, Q16(b)(iv) (1 mark): Suggest why a PCR step is usually necessary when creating a DNA profile from a crime scene sample in particular. [1]
  13. June 2024, Paper 2, Q16(c)(i) (2 marks): Suggest why some loci have two peaks but some have only one. [2]
  14. June 2024, Paper 2, Q16(c)(ii) (3 marks): Using the evidence in the DNA profile it was claimed that suspect S had been at the crime scene. Explain how strongly the evidence supports this claim. [3]
  15. June 2024, Paper 2, Q18(b)(i) (6 marks): Synthetic biology involves re-designing organisms for useful purposes. One such purpose could be the production of useful proteins. Proteins can be produced by
  16. June 2024, Paper 2, Q18(b)(ii) (1 mark): Suggest why some people might be concerned about the increase of synthetic biology. [1]
  17. June 2024, Paper 3, Q5(e)(i) (1 mark): State how a plasmid containing the gene coding for insulin can be transferred into a bacterial cell. [1]
  18. June 2024, Paper 3, Q5(e)(ii) (1 mark): Suggest how bacterial cells can be screened to check if they have taken up a recombinant plasmid. [1]
  19. June 2023, Paper 3, Q3(a)(iii) (1 mark): Often a single company holds the patent for a GM crop plant. Suggest a potential ethical issue that may exist if one company holds the patent for a GM crop plan
  20. June 2023, Paper 3, Q3(b) (3 marks): Humans have been selectively breeding maize as a crop plant for thousands of years, which has resulted in many different varieties of maize. Different varieties
  21. June 2022, Paper 2, Q12 (1 mark): Some students incubated plasmid DNA with a restriction enzyme. After 24 h they used gel electrophoresis to analyse the products of the incubation. Which option
  22. June 2022, Paper 3, Q1(d)(ii) (1 mark): State one method for inserting the AC6 gene into the heart cells during gene therapy. [1]
  23. June 2022, Paper 3, Q1(d)(iii) (1 mark): The results from gene therapy trials are published in peer-reviewed journals. State why the results from gene therapy trials are published in journals. [1]
  24. June 2022, Paper 3, Q6(a) (4 marks): Sickle cell disease (SCD) is a disease caused by the production of abnormal haemoglobin. A treatment for SCD is based on a technique called CRISPR gene editing
  25. November 2021, Paper 2, Q9 (1 mark): Which of the following substances is not required in DNA sequencing? A DNA polymerase B primers C RNA nucleotides D terminator bases Your answer [1]
  26. November 2021, Paper 2, Q10 (1 mark): DNA fragments can be separated using gel electrophoresis. Which of the following explains how gel electrophoresis is able to separate DNA fragments? A DNA carri
  27. November 2021, Paper 2, Q11 (1 mark): Gene sequencing has a number of uses. Which of the following is not a use of gene sequencing? A determining the amino acid sequence of a polypeptide B the class
  28. November 2021, Paper 2, Q16(b)(i) (4 marks): When creating a DNA profile, DNA is first extracted from a sample of tissue. Outline the subsequent steps involved in producing a DNA profile. [4]
  29. November 2021, Paper 2, Q16(b)(ii) (2 marks): Fig. 16.2 shows a DNA profile used to determine fatherhood in a paternity case. Mother M Child Ch Individual A Individual B In nd Individual C Fig. 16.2 Identif
  30. November 2021, Paper 2, Q16(b)(iii) (1 mark): DNA profiling can be used in cases of paternity and forensics. State one other use of DNA profiling. [1]
  31. November 2021, Paper 2, Q16(d) (3 marks): DNA sequencing has allowed scientists to create a strain of Escherichia coli bacteria with an entirely artificial genome. Complete the passage using the most ap
  32. November 2021, Paper 3, Q1(c)(iii) (2 marks): Explain how DNA sequencing could help scientists understand how the West Highland Terrier’s genes affect its probability of developing CPF. [2]
  33. November 2020, Paper 3, Q4(c)(i) (3 marks): Complete the diagram above by writing the missing words or phrases in the boxes labelled X, Y and Z. Answer on the diagram [3]
  34. November 2020, Paper 3, Q4(c)(ii) (1 mark): Suggest why the scientists used a plasmid that contained an antibiotic resistance gene. [1]
  35. November 2020, Paper 3, Q4(c)(iii) (2 marks): The scientists observed the following: • 1 in 400 bacteria took up the plasmid • 1 in 1000 of the plasmids taken up by bacteria contained the β‑galactosidase ge
  36. November 2020, Paper 3, Q4(c)(iv) (2 marks): A technique called quantitative PCR is used to check that the E. coli population is growing on the mice liver tumours rather than on healthy tissue. Suggest how
  37. November 2020, Paper 3, Q4(c)(v) (1 mark): Some people think that the genetic engineering of certain organisms is unethical. However, there are very few ethical concerns about the genetic engineering of
  38. June 2019, Paper 2, Q9 (1 mark): Which of the following is not a valid concern about the use of genetic modification? A that antibiotic resistance genes could transfer to pathogenic bacteria B
  39. June 2019, Paper 2, Q17(b)(i) (3 marks): The treatment of cystic fibrosis is described as somatic gene therapy. Another type of gene therapy is known as germ-line gene therapy. Complete the table below
  40. June 2019, Paper 2, Q17(b)(ii) (2 marks): Some attempts at gene therapy have resulted in changes to the functioning of other genes. Explain how inserting a new gene into a chromosome could affect the fu
  41. June 2019, Paper 2, Q17(b)(iii) (1 mark): CF occurs when individuals have two copies of a recessive allele. Huntington’s disease is a lethal disease caused by a dominant allele that codes for the protei
  42. June 2018, Paper 2, Q21(a) (1 mark): Define the term DNA sequencing. [1]
  43. June 2018, Paper 2, Q21(b) (2 marks): The speed at which DNA can be sequenced has been increasing rapidly since the introduction of DNA sequencing. The length of DNA that can be sequenced in a given
  44. June 2018, Paper 2, Q21(c)(i) (1 mark): State one development, other than nanopore technology, that has led to an increase in the speed at which DNA can be sequenced. [1]
  45. June 2018, Paper 2, Q21(d) (4 marks): DNA sequencing can be used to determine the genome of an entire organism. The first organism to have its entire genome sequenced was a virus. Ebola is a virus t
  46. June 2018, Paper 3, Q4(c)(i) (1 mark): To produce a DNA profile, DNA first needs to be purified. Explain why a protease enzyme is added to the mixture during the DNA purification process. [1]
  47. June 2018, Paper 3, Q4(c)(ii) (2 marks): DNA samples can be amplified using the polymerase chain reaction (PCR). In theory, how many fragments of DNA might be present after 12 cycles of PCR? Assume one
  48. June 2018, Paper 3, Q4(c)(iii) (1 mark): Suggest why the figure you calculated in (ii) may not be achieved in practice. [1]
  49. June 2018, Paper 3, Q4(c)(iv) (1 mark): State the name of the enzyme used in PCR to synthesise new DNA strands. [1]
  50. June 2018, Paper 3, Q4(c)(v) (2 marks): DNA fragments are separated to produce a DNA profile using electrophoresis. A student wrote the following description of the electrophoresis procedure: We will
  51. June 2017, Paper 2, Q12 (1 mark): Which of the following statements about gene therapy is not correct? A changes resulting from gene therapy cannot be passed on to offspring B germ-line gene the
  52. June 2017, Paper 2, Q21(a) (3 marks): The following passage describes steps A and B. Complete the passage using the most appropriate terms. A gene is cut from the DNA of the donor organism using a .
  53. June 2017, Paper 2, Q21(b) (3 marks): Describe the events that are taking place at the step labelled C. [3]
  54. June 2017, Paper 2, Q21(c) (3 marks): Step D results in a transformed bacterium. Many individual bacteria are not transformed successfully during this procedure. Explain how scientists can determine
  55. June 2017, Paper 2, Q21(d) (2 marks): Bacteria can be genetically modified to produce human insulin. The process is similar to that shown in Fig. 21 with some differences. First, instead of isolatin
  56. June 2017, Paper 2, Q21(e) (1 mark): Some people are concerned about genetic modification. State one valid concern that people have about the genetic modification of bacteria. [1]
  57. June 2017, Paper 3, Q1(c) (3 marks): When sequencing DNA, fragments of DNA are separated by electrophoresis. Describe three differences between the process of thin layer chromatography and the form

Questions, mark schemes and examiner’s reports are © OCR, from their published past papers. Plumi isn’t affiliated with any exam board. Want whole papers? Every OCR A-Level Biology A paper, or our free OCR-style practice pack.

Rather write your answers by hand on iPad? Plumi marks them against the same mark schemes.