List the stages of mitosis, and briefly describe the appearance/position of the chromosomes at each stage.

The stages of mitosis are as follows: prophase; prometaphase; metaphase, anaphase and telophase.

Explanation:

  In the prophase phase, the cytoplasm becomes denser, increasing its volume, as it gave water to the nucleus. This fact causes the cytoplasm to become denser, as wrote before. At the beginning of the prophase each chromosome is constituted by two filaments called chromats, joined by the centromere.

  As the prophase progresses, the chromosomes become short and increase in thickness. It is chromosomal spiraling. The same time the chromosomes are condensing, the nucleolus begins to become less evident, disappearing at the end of the prophase.

  In the prometaphase, the library crumbles and when this happens, the chromosomes fall into the cytoplasm and travel to the equatorial region of the cell, where the spindle fibers will be attached by centromere.

  In metaphase, chromosomes are located in the central part of the cell, more condensed and linked to the spindle by the centromere. It is at this stage that scientists use, mainly in plants, to perform chromosome counting and thus carry out chromosome studies.

 The Anaphase stage begins at a time when the centromere of each duplicated chromosome divides longitudinally, separating the sister chromatids. As soon as they separate, the chromatids are referred to as the sister chromosomes, and are pulled to the opposite poles of the cell, oriented by the spindle fibers. Once the sister chromosomes reach the opposite poles of the cell, the phase of anaphase ceases to begin the next.

 The next stage is called telophase and is the last one about mitosis. In this phase, the library reorganizes, the chromosomes deconcentrate, the kinetochore and cimetochoric fibers disappear and the nucleolus reorganizes and so the cell prepares for division, where a cell will divide into two and thus a cell giving rise to two, two to four, and so on.

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