Crossing over is one of the most important events in meiosis because
A) it produces new combinations of alleles on chromosomes.
B) separation of homologous chromosomes occurs.
C) separation of sister chromatids occurs.
D) it results in the production of haploid gametes.
E) it aligns homologous chromosomes at the center of the cell so that they can be separated in anaphase II.

Question

Quizplus · Accepted Answer

Crossing over is the exchange of genetic material between homologous chromosomes during prophase I of meiosis. This process results in new combinations of alleles on chromosomes, which increases genetic diversity and variation within a population. Therefore, option A is correct. The other options are not entirely accurate:

B) Separation of homologous chromosomes occurs during anaphase I, not crossing over.

C) Separation of sister chromatids occurs during anaphase II, not crossing over.

D) Crossing over does not directly result in the production of haploid gametes, but it does contribute to the genetic diversity of haploid gametes produced by meiosis.

E) Aligning of homologous chromosomes at the center of the cell occurs during metaphase I, not crossing over.

Crossing Over Is One of the Most Important Events in Meiosis