MitosisMitosis is the process in which the DNA in the nucleus of a cell is duplicated into two indentical sets in the form of chromosomes. These two sets of chromosomes form their separate nuclei, one in each of the two new cells created during the end of the mitotic phase. Mitosis begins as DNA from one cell duplicates within its nucleus during the interphase. The DNA then condenses into chromosomes (each chromosome containing 2 identical chromatid) whilst the nuclear membrane starts deteriorating. Two centrioles drift towards opposite sides of the cell, each attached to the centromeres of the chromosomes with the mitotic spindle. The chromosomes then line themselves up in the middle of the cell and each chromosome is then divided into single-strand chromatids and one of every pair is pulled to each of the centrioles. The separated sets of chromosomes then form their own nuclear membranes followed by cytokinesis.
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MeiosisMeiosis involves cytokinesis such as that in Mitosis, but the daughter cells produced by one parent cell are not identical to the parent nor each other unless in Parthenogenesis where the mother contributes all the genetic information creating female offspring. This process begins as a single diploid parent cell undergoes meiosis to create gametes (sperm in males and eggs in females), usually numbering four sperm from each male cell and one egg from each female cell. Firstly each pair of chromosomes in the cell, consisting of one maternal and one paternal chromosome from the mother and father, replicate. These chromosomes then pair off, one maternal chromosome with one paternal chromosome. These chromosomes then exchange DNA. Afterwards, centrioles with spindle fibers are attached to the centromeres of each chromosomes align them in the equator of the cell and then pull each pair chromosomes apart to opposite ends of the cell which then undergoes cytokinesis. The chromosomes of each diploid daughter cell are then separated again by spindle fibres into separate chromatids which are pullted apart to each end of the cell and cytokinesis occurs for the final time, the result being four gamete cellls
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Binary FissionBinary fission is the asexual reproduction process in prokaryotic cells such as those in the Archaea & Bacteria kingdoms where a cell is duplicated. The DNA in the cell is replicated but does not form into chromosomes or chromatids such as that in Mitosis or Meiosis. The duplicated strand of DNA are then separated as the cell elongates and eventually splits as the cell wall "invaginates", meaning it grows inward near the center of the cell. These two daughter cells are indentical to the parent and have the capacity to grow into the full size of the parent cell.
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