The events that occur in meiosis but not mitosis include homologous chromosomes pairing up, crossing over, and lining up along the metaphase plate in tetrads.The daughter cells produced by mitosis are identical, whereas the daughter cells produced by meiosis are different because crossing over has occurred.In mitosis, the daughter cells have the same number of chromosomes as the parent cell, while in meiosis, the daughter cells have half the number of chromosomes as the parent. For the most part, in mitosis, diploid cells partition into two new diploid cells, while in meiosis, diploid cells partition into four new haploid cells.Meiosis II is, thus, referred to as equatorial division. Meiosis II is not a reduction division because, although there are fewer copies of the genome in the resulting cells, there is still one set of chromosomes, as there was at the end of meiosis I. They are different because there has been at least one crossover per chromosome. The two daughter cells of mitosis, however, are identical, unlike the daughter cells produced by meiosis. During anaphase II and mitotic anaphase, the kinetochores divide and sister chromatids, now referred to as chromosomes, are pulled to opposite poles. In this case, the duplicated chromosomes (only one set, as the homologous pairs have now been separated into two different cells) line up on the metaphase plate with divided kinetochores attached to kinetochore fibers from opposite poles. Meiosis II is much more similar to a mitotic division. The daughter cells resulting from mitosis are diploid and identical to the parent cell. The four daughter cells resulting from meiosis are haploid and genetically distinct. There is no such reduction in ploidy level during mitosis.Ĭomparing Meiosis and Mitosis : Meiosis and mitosis are both preceded by one round of DNA replication however, meiosis includes two nuclear divisions. For this reason, meiosis I is referred to as a reduction division. When the tetrad is broken up and the homologous chromosomes move to opposite poles, the ploidy level is reduced from two to one. As a chiasmata develops, crossing over occurs between homologous chromosomes resulting in recombinant chromosomes. The main differences between mitosis and meiosis occur during meiosis I where the homologous chromosome pairs become associated with each other and are bound together with the synaptonemal complex. In contrast, t he nuclei resulting from meiosis is half the number of chromosome sets in the original cell, which is diploid. Furthermore, the two nuclei in mitosis have the same number of sets of chromosomes, one set in the case of haploid cells and two sets in the case of diploid cells. In meiosis, the two nuclear divisions result in four nuclei that are not genetically identical and contain one chromosome set only that usually divide into four new haploid daughter cells. Mitosis is a single nuclear division that results in two nuclei that are genetically identical to the original parent nucleus. The purpose of mitosis is cell regeneration, growth, and asexual reproduction, while the purpose of meiosis is the production of gametes for sexual reproduction. They share some similarities, but also exhibit distinct differences that lead to different outcomes. Mitosis and meiosis are both forms of division of the nucleus in eukaryotic cells. Mitosis and meiosis share some similarities but also some significant differences, chiefly that mitosis produces genetically identical diploid daughter cells where as meiosis produces genetically different haploid cells.
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