Mitosis is the scientific term for nuclear cell division, where the nucleus of the cell divides, resulting in two sets of identical chromosomes. Mitosis is accompanied bycytokinesis in which the end result is two completely separate cells called daughter cells. There are four phases of mitosis: prophase, metaphase, anaphase and telophase.
The first phase of mitosis is prophase. In this phase the chromosomes which are normally spread throughout the nucleus begin to condense into a tight ball. The DNA molecules of the chromosomes begin to interact with enzymes and proteins that assist in the replication of the genes. The compact coiling of the chromosomes at this stage of mitosis is called mitotic chromosomes. Nearing the end of prophase, the material enclosing the nucleus and the cytoskeleton disappears. The cytoskeleton is transformed into what is called a spindle apparatus which works to pull the duplicated chromosomes apart during the anaphase.
The second phase of mitosis is metaphase. In this phase the chromosomes of the dividing cell begin to line up and are coordinated with the spindle apparatus. The soon to be divided chromosomes are symmetrically positioned on the metaphase plate typically at the equator of the parent cell.
Anaphase is the third step of mitosis. Abruptly the spindle apparatus pulls the two identical sets of chromosomes apart from one another. Each new set of chromosomes is moved to opposite spindle poles. These two sets of chromosomes will soon develop into the nuclei of two daughter cells perfectly identical to each other as well as identical to the parent cell.
The final stage of mitosis is telophase which means end. Telophase is best described as the opposite of prophase. As the chromosomes begin to move toward the spindle pole they start to uncoil and spread out. Then the spindle apparatus made of the former cytoskeleton is deconstructed. Finally the nuclear envelope or membrane is formed around the chromosomes. Although this is the last phase of mitosis, telophase will not be complete until cytokinesis has been carried out. Cytokinesis is similar to mitosis except it involves the cell’s cytoplasm and organelles where mitosis is the division of the nucleus or control center of the cell. Once mitosis and cytokinesis are properly completed there are two new functioning cells.
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