![]() ![]() ![]() The cell then divides into two haploid daughter cells by cytokinesis. 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. Prophase II is similar to prophase in mitosis in that there is the break down. During this stage, the spindle fibers, or microtubules, attach to the centromere of each chromosome. In anaphase I sister chromatids are still intact and connected at the centromere. 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. 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. Notice that for both chromosomes 1 and 2, the paternal chromosome is on the. The first stage of Meiosis I is prophase I. During prophase 1, enzymes find each member of the homologous pair and pair. Meiosis is divided into two phases, beginning with Meiosis I. Condensation of chromosomes This is a mechanism that involves the condensing of the DNA that is synthesized during interphase. The DNA in the cell is replicated during the S, or Synthesis, stage. In animal cells, prophase is the first phase of mitosis and the second phase of mitosis in plant cells. Prophase 1 and 2 movie#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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