Q24 · 2024 · Paper 1Unclassified3 marks
QUESTION 24 (3 marks)
The diagram shows a process that occurs during meiosis.
a) Identify the process.
[1 mark]
b) Explain how this process contributes to genetic variation in the genotypes of offspring.
[2 marks]
WORKED SOLUTION
3 marksQCAA guide · typeset solution
QCAA sample response and mark allocation
24a) | Crossing over | • identifies crossing over [1 mark] |
24b) | Crossing over involves homologous chromosomes exchanging portions of their DNA. Because homologous chromosomes have the same genes but (usually) different alleles, this results in chromosomes with new combinations of genetic information/alleles. | • describes crossing over [1 mark] • explains how crossing over contributes to genetic variation [1 mark] |
QCAA sample response and marking criteria reproduced from the official guide.
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