Question

Which of the following best describes what happens during a cross-over event?

A. Tetrads change orientation as they line up along the center of the cell.
B. Chromatids of homologous chromosomes exchange corresponding segments. C. X and Y sex chromosomes overlap and combine together during metaphase. D. Spindle fibers overlap and attach to the wrong chromosomes during anaphase.

Answer 1

b. Chromatids of homologous chromosomes exchange corresponding segments.

Answer 2

The answer is B. Chromatids of homologous chromosomes exchange corresponding segments
The crossover in this context is the exchange of genetic material between homologous chromosomes. Homologous chromosomes are only present in the meiosis I, but not in meiosis the II. Because of the crossovers, now a new and unique gene combination is created resulted in completely unique individual