How does meiosis contribute to genetic variation among gametes (sperm and egg cells)?
Answer and explanation
Correct answer: B. Through crossing over (recombination) in prophase I and independent assortment of homologous chromosomes in metaphase I
- Step 1: Crossing over exchanges genetic segments between non-sister chromatids of homologous chromosomes, creating recombinant alleles. Step 2. Independent assortment randomly orients maternal and paternal chromosomes at the metaphase plate, yielding 2^n unique combinations. Answer: Through crossing over (recombination) in prophase I and independent assortment of homologous chromosomes in metaphase I. Why not the others: Mitosis produces identical clones; meiosis creates variation.
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