CAIE A Level Biology 9700 · Inheritance
A species of plant has a diploid chromosome number of 8 (2n = 8).
Explain why the number of genetically different gametes that a single individual of this species can produce is far greater than the number predicted by considering only the independent assortment of homologous chromosomes. Your answer should include the roles of crossing over during meiosis and random fusion of gametes at fertilisation.
6 marks, so the mark scheme is looking for about 6 separate creditworthy points. Making the same point twice in different words earns it once.
Explain means: Give the reasons or the mechanism: why or how something happens. Link each point to the next with because, so or which means. A list of facts with no links usually loses the reasoning marks.
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