Answer:
The cell cycle represents about 90% of mitosis.
Explanation:
The cell starts the process resulting in division. The entire cell cycle may be considered to be in four phases; G1, S, G2, and M. In the G1 phase, the cell doubles in size, and there is formation of new organelles and materials required for two cells. During this phase, there is nucleus migration to the center of the cell. This phase ends with the G1/S checkpoint. The process can be terminated at this point, or proceed to S phase in which DNA and associated nuclear proteins are replicated. By the end of the S phase, the cell contains two entire copies of its genetic information. The cell proceeds to G2 phase where the chromosome starts condensing, and structures required for division are formed. A discrete band of microtubules forms around the cytoplasm marking the plane of cell division. At the end of the G2 phase, the cell undergoes another checkpoint: G2/M checkpoint, upon which, if conditions are appropriate, the cell enters M phase in which it divides.
