4. The stage of mitosis that is shown below is known as prophase.
It is prophase as the chromosomes have become visible as a
mass of twisted black lines at the middle of the cell.
Briefly written, the DNA & associated proteins begin to
condense and become visible during prophase. The replicated centrioles begin
to migrate to opposite poles and microtubules begin to radiate from each centriole
to form the spindle. The nucleolus disappears and then the nuclear envelope
disappears. Finally, the sister chromatids begin to migrate towards the equator.
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