1. PROPHASE
During prophase, chromosomes replicated in interphase begin to condense into compact, rod like structures. The nucleolus becomes smaller and eventually disappears in some species. This reflects the shutdown of all RNA synthesis. In the cytoplasm, the MITOTIC SPINDLE begins to form between the two centrosomes as they start to migrate toward opposite poles of the cell to form SPINDLE POLES.
2. PROMETAPHASE
Once the nuclear envelope breaks down, initiates Prometaphase. Bundles of spindle microtubules grow from the centrosomes at the opposing spindle poles toward the centre of the cell. The sister chromatids are held together by the CENTROMERES. At this time, a complex of several proteins , A KINETOCHORE, has formed on each chromatid at the centromere. Kinetochore microtubules bind to the kinetochore where they attach each sister chromatid to microtubules at the opposite end of the pole. NONKINETOCHORE MICROTUBULES extend between the spindle poles without connecting to chromosomes but rather overlap from one pole to another
3. METAPHASE
The spindle reaches its final form and the spindle microtubules move the chromosomes into alignment at the spindle midpoint, also called METAPHASE PLATE. Only when the chromosomes are all assembled at the spindle midpoint with the two sister chromatids of each one attached to the microtubules, leading to opposite spindle poles can metaphase give away the separation of chromatids.
4. ANAPHASE
Sister chromatids separate and move to opposite spindle poles. The first sign of chromosome movement can be seen at the kinetochores as they move to opposite poles. The movement continues until the separated chromatids called DAUGHTER CHROMOSOMES.
5. TELOPHASE
The spindle disassembles and the chromosomes at each spindle pole decondense and return to the extended state similar to interphase. As decondensation proceeds, the nucleolus reappears, RNA transcription resumes and a new nuclear envelope forms around each pole, producing two daughter nuclei.
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