Question

Describe what happens during each of the following Mitosis stages

Prophase:
Prometaphase:
Metaphase:
Anaphase:
Telophase:
Cytokinesis:

Answer 1

Answer : The mitotic cell division was first explained by W. Flemming in 1882. It consists of four sub-stages:

1. Prophase : Each of the available chromosome becomes individual long thread like structure when the chromatin network begins to coil. They will have two chromatids held together by centromere. The nucleus and the nuclear membrane gradually disappears in this stage.
2. Metaphase : The metaphase stage begin when the nucleus and the nuclear membrane disappears. The chromosomes also becomes shorter by coiling. All the centromeres arrange themselves in the equator forming metaphase plate or equatorial plate. The chromosomes become visible and both the chromatids in each chromosome face the opposite poles. In this phase the spindle fibres are seen arising out of the centromeres. Now the centromeres are ready to divide and the two chromatids would seperate.
3. Anaphase : The anaphase stage begins once the centromere divides. The spindle fibres contract and the chromosomes assume V or J or I shaped structures. They are due to the variable position of the centromeres.
4. Telophase : The chromosome begin to uncoil, elongate and become invisible. The nuclear membrane and the nucleolus reappear. By the end, two daughter nuclei are formed, one at each pole.

  Cytokinesis : Cytokinesis means division of the cytoplasm. A cell wall is formed around the daughter nuclei. The golgi bodies helps in generating the cell membrane. Hence, by the end of the mitosis two identical daughter cells are formed.

Note: Division of cytoplasm is cytokinesis whereas the division of nucleus is Karyokinesis.