P= Prophase: the nuclear envelope disappears and replicated chromosomes coil together into X - shaped chromosomes.
M= Metaphase: the tugging of the spindle fibres pulls the chromosomes into a single line across the middle of the cell.
A= Anaphase: The spindle fibres begin to contract and shorten. This action pulls the centromere apart, allowing the sister chromatids to move to opposite pole of the cell. Once they separate, each sister chromatid is considered as a chromosome.
T= Telophase: final stage of mitosis. one complete set of chromosomes stand at each pole of the cell. the spindle fibres begin to disappear, and a nuclear membrane forms around each set of chromosomes. Now there are two nuclei in one cell. the cell is ready to divide.
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