![]() ![]() This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License. Prophase 1 is the initial phase of meiosis 1 and prophase 2 is the initial phase of meiosis 2. Two stages of meiosis can be distinguished, meiosis 1 and meiosis 2. The cell then divides into two haploid daughter cells by cytokinesis. Prophase 1 and 2 are two phases in the meiotic division of cells that produce gametes in order to carry out their sexual reproduction. In telophase I, the microtubules break down, the nuclear membrane reforms, and the chromosomes return to an uncondensed state. The last stage of Meiosis I is telophase I. It is important to note that the sister chromatids remain attached at the centromere of each chromosome. Here the homologous chromosome are pulled apart to opposite ends of the cell. The chromosomes are then aligned at the equator, or mephase plate, of the cell. 1.1 Prophase I 1.2 Prometaphase I 1.3 Metaphase I 1.4 Anaphase I 1.5 Telophase I and Cytokinesis I 2 Meiosis II. During this stage, the spindle fibers, or microtubules, attach to the centromere of each chromosome. This exchange is called recombination, or crossing over.Īt the end of prophase I, the nuclear membrane breaks down, the centrosomes have migrated to the opposite ends of the cell, and the spindle apparatus is being formed. Prophase II is much shorter than prophase I (Meiosis I), primarily because no further genetic reassortment, or crossover, takes place. This is followed by an exhange of DNA between non-sister chromatids. During the beginning of this stage, the chromosomes condense.ĭuring the middle of prophase I, homologous chromosome undergo synapsis, or pairing up. During the prophase I (PI) of meiosis, homologous chromosomes undergo pairing, synapsis, and meiotic recombination (1, 2). The first stage of Meiosis I is prophase I. Meiosis is divided into two phases, beginning with Meiosis I. ![]() The DNA in the cell is replicated during the S, or Synthesis, stage. See the Flash movie for the following sequence of images,īefore meiosis begins, the diploid germline cell goes through the three stages of interphase: G1, S, and G2. ![]() Thumbnail images will bring up a larger, labeled version of the During this phase the chromosomes in the diploid cell synapse, undergo recombination, and are finally separated into two new haploid daughter cells. Meiosis I is the first cell division event in meiosis. Meiosis is a key process of sexual reproduction. ![]()
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