Question

The inactivation of M-Cdk leads to which of the following?Choose one:

A. onset of G2 phase
B. onset of mitosis
C. onset of S phase
D. exit from mitosis
E. exit from S phase

Answer 1

The inactivation of M-Cdk leads to the cell's exit from mitosis, which is essential for the proper progression of the cell cycle.

Step-by-step explanation:

The inactivation of M-Cdk (maturation-promoting factor, also known as mitosis-promoting factor) leads to D. exit from mitosis. M-Cdk is a cyclin-dependent kinase that is essential for a cell to progress from the G2 phase into mitosis. When M-Cdk is active, it triggers a cascade of events that initiate mitosis. Inhibiting or inactivating M-Cdk prevents the cell from entering mitosis or promotes exit from mitosis if the cell is already in that phase, thus ensuring that the cell cycle progresses appropriately. Errors in M-Cdk function can lead to uncontrolled cell division, which is a characteristic of cancerous cells.