Question

Which of the following best describes how crossing over occurs during meiosis?

A. During prophase I, homologous chromosomes are lined up and pulled apart to opposite poles.
B. During prophase I, segments of chromatids are exchanged between homologous chromosomes.
C. During prophase II, chromosomes overlap and sections of each chromosome switch places.
D. During prophase II, sister chromatids trade places with each other before metaphase begins.

I think this one is either A or B but im leaning towards B?

Answer 1

you're on the right track. but the answer should be B. crossing over occurs in meiosis 1 and by definition crossing over is the exchange of genetic material of non-sister chromatids of the homologous chromosomes. it usually occurs in prophase 1 of meiosis. the reason why i wouldn't choose A is because A describes the chromosomes at the metaphase plate which occurs after crossing over if any