Question

choose whether the following statements about crossing over is true or false. as a result of crossing over, sister chromatids from the same homolog are no longer identical to each other. for crossing over to occur, homologous chromosomes must align precisely in prophase i so that their chromatids can exchange corresponding segments of dna. crossing over prevents homologous chromosomes from separating during meiosis i. crossing over creates genetic variation by creating 2 recombinant chromosomes. if crossing over did not occur, the outcome of meiosis i would be 2 diploid cells.

Explanation:

1. During crossing - over, genetic material is exchanged between non - sister chromatids of homologous chromosomes, so sister chromatids from the same homolog are no longer identical. True.
2. For crossing - over to occur, homologous chromosomes must precisely align in prophase I to enable DNA segment exchange. True.
3. Crossing - over does not prevent homologous chromosomes from separating in meiosis I; rather, it can facilitate proper alignment and segregation. False.
4. Crossing - over creates genetic variation by generating recombinant chromosomes. True.
5. If crossing - over did not occur, meiosis I would still result in haploid cells, not diploid cells. False.

Answer:

1. True
2. True
3. False
4. True
5. False