Cell would normally proceed to mitosis without interruption

Options

A. once it has entered the S phase
B. once it has entered the `G_(2)` phase
C. at any time during cell division activity
D. none of these

Answer

A

Explanation

The availability of mitogen and energy rich compounds decide wheter `G_(1)` phase will be arrested (`G_(0)` phase) or undergo S-phase. This point is called check point or `G_(1)` cyclin or `G_(1)` point. Once the check point of `G_(1)`-phase is crossed and cell has entered S-phase, cell cycle will go on further division till completion.