Question

1. when does crossing over occur? mitosis meiosis chiasma chromatid clear all

Explanation:

Crossing over is a key event in meiosis. In meiosis, homologous chromosomes pair up during prophase I. During this pairing, segments of non - sister chromatids exchange genetic material through crossing over. Mitosis is a process of cell division for growth and repair where genetic material is replicated and divided equally without crossing over. Chiasma is the physical site of crossing over, not the process where crossing over occurs. Chromatid is a part of a chromosome (after replication, a chromosome has two sister chromatids).

Answer:

meiosis