What is Mitosis?
There are various structures within the cell, but many are too difficult to see. For example, within the nucleus lie the chromosomes. These are important for heredity and reproduction. When a cell splits and becomes two, certain processes occur within the nucleus first. One of these processes involves the splitting of the chromosomes. This process is called Mitosis and there are four distinct stages. Mitosis takes place in Regular Body Cells or Somatic Cell. It keeps Cells Living and Growing.
Events during Mitosis
| Interphase: Cells may appear inactive during this stage, but they are quite the opposite. This is the longest period of the complete cell cycle during which DNA replicates, the centrioles divide, and proteins are actively produced.
| Prophase: During this first mitotic stage, the nucleolus fades and chromatin (replicated DNA and associated proteins) condenses into chromosomes. Each replicated chromosome comprises two chromatids, both with the same genetic information. Microtubules of the cytoskeleton, responsible for cell shape, motility and attachment to other cells during interphase, disassemble. And the building blocks of these microtubules are used to grow the mitotic spindle from the region of the centrosomes.
| Prometaphase: In this stage the nuclear envelope breaks down so there is no longer a recognizable nucleus. Some mitotic spindle fibers elongate from the centrosomes and attach to kinetochores, protein bundles at the centromere region on the chromosomes where sister chromatids are joined. Other spindle fibers elongate but instead of attaching to chromosomes, overlap each other at the cell center.
| Metaphase: Tension applied by the spindle fibers aligns all chromosomes in one plane at the center of the cell.
| Anaphase: Spindle fibers shorten, the kinetochores separate, and the chromatids (daughter chromosomes) are pulled apart and begin moving to the cell poles.
| Telophase: The...
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