During meiosis, what process involves the exchange of genetic material between homologous chromosomes?

During meiosis, what process involves the exchange of genetic material between homologous chromosomes?

• A. Segregation
• B. Independent assortment
• C. Crossing over
• D. Replication

Answer: (C)

Crossing over is the exchange of genetic material between homologous chromosomes, and it happens during prophase I of meiosis when homologs pair up and form a tetrad. Non-sister chromatids of those homologs physically swap segments, creating recombinant chromatids with new combinations of alleles. This is the mechanism that generates genetic variation in gametes. Segregation refers to the separation of homologous chromosomes to opposite cells, not a DNA exchange. Independent assortment describes how different chromosome pairs orient randomly during meiosis I, also not about exchanging genetic material. Replication is the duplication of DNA that occurs earlier in the cell cycle, before meiosis begins.

Crossing over is the exchange of genetic material between homologous chromosomes, and it happens during prophase I of meiosis when homologs pair up and form a tetrad. Non-sister chromatids of those homologs physically swap segments, creating recombinant chromatids with new combinations of alleles. This is the mechanism that generates genetic variation in gametes. Segregation refers to the separation of homologous chromosomes to opposite cells, not a DNA exchange. Independent assortment describes how different chromosome pairs orient randomly during meiosis I, also not about exchanging genetic material. Replication is the duplication of DNA that occurs earlier in the cell cycle, before meiosis begins.