We can compare mitosis and meiosis. Meiosis halves the total number of chromosomes, reducing the number of sets of chromosomes from two (diploid) to one (haploid), with each daughter cell receiving one set. Mitosis conserves the number of chromosome sets. Meiosis produces cells that differ genetically from the parent cell and from each other. Mitosis produces daughter cells that are genetically identical to the parent cell and to each other. Three events unique to meiosis occur during meiosis I: 1. Synapsis and crossing over o During prophase I, replicated homologs pair up and become physically connected along their lengths by a zipperlike protein structure, the synaptonemal complex , in a process called synapsis. o Crossing over , genetic rearrangement between nonsister chromatids, occurs during this stage. o Following disassembly of the synaptonemal complex in late prophase, the two homologs pull apart slightly but remain connected by at least one X-shaped region called a chiasma (plural,
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