Question

Does crossing over happen between sister chromatids or homologous chromosomes? Know that crossing over produces recombinant chromosomes which increases the variation of gametes.

a) Crossing over happens between sister chromatids and does not increase genetic variation.
b) Crossing over happens between homologous chromosomes and increases genetic variation.
c) Crossing over happens between sister chromatids and increases genetic variation.
d) Crossing over happens between centromeres and does not affect genetic variation.

Answer 1

Crossing over occurs during meiosis in prophase I and involves the exchange of genetic material between non-sister chromatids of homologous chromosomes. This process increases genetic variation in gametes.

Step-by-step explanation:

Crossing over occurs during meiosis, specifically in prophase I, and it involves the exchange of genetic material between non-sister chromatids of homologous chromosomes. During prophase I, homologous chromosomes line up in pairs, known as tetrads, and genetic material can be exchanged between the chromatids, resulting in recombinant chromosomes. This process increases genetic variation in gametes.