Which two processes in meiosis produce genetic variation between gametes?
Answer and explanation
Correct answer: A. Crossing over in prophase I and independent assortment in metaphase I
- Step 1: Crossing over exchanges alleles between homologous chromatids. Step 2. Random orientation of bivalents gives different combinations of maternal and paternal chromosomes. Answer: Crossing over in prophase I and independent assortment in metaphase I. Why not the others: replication and cytokinesis do not shuffle alleles; crossing over occurs in prophase I; independent assortment of homologues occurs in meiosis I.
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