Meiosis is a way cells divide. The purpose of meiotic cell division is to create genetic variation, therefore not all cell divisions occur meiotically. The cells that divide by means of Meiosis is gametes, also called gametes. Gametes are found in all organisms that divide sexually. In animals, the gametes are called eggs and sperm, while in plants an egg is also found, but instead of sperm, plants use pollen.
Cells that divide with meiosis go through two stages of division (mitosis goes through only one). In the first phase of division, the chromosomes are copied via DNA replication and placed in the center of the cell. There is a crossover event, where DNA, and thus genes, are exchanged among the different chromosomes. It is this crossover that provides genetic variation. After the exchange of DNA, cells divide as it normally would in mitosis. The two daughter cells are now going through the second division phase. Unlike the first division phase, there is no DNA replication in the second division phase. In the second phase of division, the two diploid cells divide and become four haploid cells. These four haploid cells are gametes, and they all contain a unique copy of each chromosome. Gametes are now ready to splice themselves with another haploid cell using a haploid cell. sexual reproduction and turn into a diploid cell called zygote.
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