Cell Cycle and Cell Division Question 1
1. Some dividing cells exit the cell cycle and enter vegetative inactive stage. This is called quiescent stage $(G_0)$. This process occurs at the end of
(a) $G_1$ phase
(b) $S$ phase
(c) $G_2$ phase
(d) M phase
Show Answer
Answer : d
Hints & Solutions
(d) Some dividing cells exit the cell cycle and enter vegetative inactive stage, called quiescent stage $(G_0)$. This process occurs at the end of $M$-phase and beginning of $G_1$ phase. Human cancers have an apparent low growth fraction, the bulk of cells presumed to being out of cycle in a $G_0$ quiescent state due to the inability in the past to distinguish $G_0$ from $G_1$ cells. Thus, human cancers are blocked in transition in $G_1$ and are not predominantly in a $G_0$ or quiescent differentiated state.
