The two chromatids will then separate and segregate to two daughter cells. ![]() The chromatids, though, remain together so each of the newly formed daughter cells will contain one of the homologous chromosomes with two chromatids by the end of meiosis I. The chromosomes start to pair with each other and eventually segregate into two cells. After the completion of S phase and the production of identical chromatids from the replication of the parent chromosome, meiosis I commence. The two succeeding chromosomal divisions result in the halving of the original number of chromosomes. This means that the different events during the pairing of chromosomes, such as the recombination of reciprocal, the crossing-over, and the formation of chiasma are connected therefore, the only successful process of recombination at meiosis I prophase will be the one that produces the correct homologous chromosome segregation at meiosis I. Moreover, it should be noted that these events are interdependent. These various behaviors of the chromosome are described below for the distinctive events happening in each meiosis stage. Then, the two sister chromatids separate during meiosis II. ![]() These features allow the homologous segregation on the mitotic spindle. The release of the cohesion sister chromatids in a two-step process occurs in Meiosis I.Meiosis I has the pairing of the homologous chromosome.Meiosis I has reciprocal recombination (may also be called chiasma formation and crossing over).Meiosis I can be distinguished from mitosis by three main features: ![]() The behavior and organization of the chromosomes differ in each stage, which gives clues about the complexity of prophase I. Prophase I, in particular, occupies almost more than half the time taken for meiosis as it contains 5 substages: leptotene, zygotene, pachytene, diplotene, and diakinesis. meiosis I) is the most complicated part of the meiotic division. ![]() Each part consists of 4 phases ( prophase, metaphase, anaphase, and telophase), which is similar to mitosis by being comprised of four phases. The process of meiosis is divided into 2 parts, meiosis 1 and 2. Consequently, during fertilization when the two haploid cells fuse, the number of chromosomes in the produced cell is restored as somatic cells (each with 46 chromosomes). So the number of chromosomes in meiosis decreases to half. In the human body, the meiosis process takes place to decrease the number of chromosomes in a normal cell which is 46 chromosomes to 23 chromosomes in eggs and sperms. The main function of the meiotic division is the production of gametes (egg cells or sperm cells) or spores. Etymology: from Greek meiōsis, meioun (to diminish), from meiōn (less). Meiosisis a form of cell division in sexually reproducing organisms wherein two consecutive nuclear divisions (meiosis I and meiosis II) occur without the chromosomal replication in between, leading to the production of four haploid gametes, each containing one of every pair of homologous chromosomes (that is, with the maternal and paternal chromosomes being distributed randomly between the cells).
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