AP BIOLOGY

LABORATORY REVIEW

MITOSIS AND MEIOSIS

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Question [CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]

Crossing over takes place during which phase of Meiosis?

A	anaphase
B	metaphase II
C	telophase
D	prophase I

Explanation:

Detailed explanation-1: -Crossing over is an enzyme-mediated process, where the exchange of genetic material between non-sister chromatids of homologous chromosomes takes place. It occurs at the pachytene stage of prophase I of meiosis.

Detailed explanation-2: -Crossing over occurs during the pachytene stage of prophase in meiosis, however the chiasma are visible during. No worries!

Detailed explanation-3: -Explanation: During prophase I, homologous chromosomes pair with each other and exchange genetic material in a process called chromosomal crossover. The exchange occurs in segments over a small region of homology (similarity in sequence, ie., the same alleles).

Detailed explanation-4: -During meiosis, crossing-over occurs at the pachytene stage, when homologous chromosomes are completely paired.

There is 1 question to complete.