The Cell Cycle

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Cell Cycle

Divide, Grow and Redivide

1. First Growth Phase ( G1 )

The volume of cytoplasm increases.

Mitochondria and chloroplasts divide.

They may either withdraw from the cell cycle and enter a resting phase, or:

Start preparing for the next division by entering the synthesis phase.

2. Synthesis Phase ( S )

More DNA is synthesized, the chromosomes are duplicated.

3. Second Growth Phase ( G2 )

This is a shorter growth phase, in which RNA and proteins necessary for cell division continue to be synthesized.

Now, the cell is ready to start cell division and thus the cell cycle goes on.

Mitosis