Friday, August 12, 2011
Please help me with this paragraph? its about mitosis?
Division consists of mitosis and cytokinesis or cytoplasmic division. Mitosis is divided in four stages known as prophase, metaphase, anaphase and telophase. In prophase, the chromosomes in the nucleus condense to form visible chromatids. These chromatids have two strands of the condensed chromosomes with a centomere joining them together. The microtubules produced from interphase forms a three-dimensional structure called spindle. The spindle fibres attaches to the centromere of the chromosomes at the equator of the cell. This completes the stage of metaphase. In anaphase, the spindle fibres pull the two halves of each centromere to the opposite direction. Anaphase is completed when the separated chromatids reach the opposite ends of the cell and the spindle fibres breaks down. The last stage, telophase, the chromosomes unravel while the nuclear envelop reforms thus creating two identical nucleus in the cell. Cytokinesis has started during the beginning of the telophase; this is the final stage of division where the cell membrane constricts around the centre of the cell until the two identical daughter cells are formed.
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