Question

which event happens in meiosis ii but not in meiosis i?a. spindle microtubules attach to centromeres.b. crossing over occurs.c. sister chromatids move to opposite poles.d. chromosomes become shorter and thicker by coiling.

Answer 1

The correct answer is C. Sister chromatids move to opposite poles. This is because in meiosis I, homologous chromosomes separate, while in meiosis II, sister chromatids separate, resulting in the production of haploid gametes with half the chromosome number of the parent cell. During meiosis I, spindle microtubules attach to homologous chromosomes, allowing them to separate, and crossing over occurs between homologous chromosomes, resulting in genetic diversity.

In meiosis II, spindle microtubules attach to sister chromatids, pulling them apart to opposite poles of the cell. Chromosomes do become shorter and thicker by coiling during both meiosis I and II, but this is not a distinguishing event between the two.