Question

Which of the following events of meiosis creates genetic variation among the gametes?

1) crossing over
2) random separation of maternal and paternal chromosomes
3) distribution of differing numbers of chromosomes to daughter cells
4) both a and b
5) all of the above

Answer 1

The events in meiosis creating genetic variation among gametes are crossing over and random separation of maternal and paternal chromosomes. Crossing over during prophase I and random assortment of tetrads on the metaphase plate both ensure unique genetic combinations in each gamete.

Step-by-step explanation:

The events of meiosis that create genetic variation among the gametes are crossing over and the random separation of maternal and paternal chromosomes. During prophase I of meiosis I, crossing over occurs between nonsister chromatids of each homologous pair, leading to recombinant chromatids with new combinations of maternal and paternal genes. The random assortment of tetrads on the metaphase plate during meiosis I also contributes to variation, by ensuring a unique mix of chromosomes ends up in each gamete. Hence, the correct answer to the student's question is both a and b, which corresponds to options 1) crossing over and 2) random separation of maternal and paternal chromosomes.