Once a cell enters mitosis, the molecules that activate division must be turned off. What happens to MPF during mitosis?
A) It is completely degraded.
B) It is phosphorylated by a Cdk, which inactivates it.
C) The cyclin component of MPF is degraded.
D) The Cdk component of MPF is degraded.

Question

Quizplus · Accepted Answer

The cyclin component of MPF is degraded during mitosis, leading to the inactivation of MPF and the progression of the cell into cytokinesis. This degradation is regulated by proteasomes, which selectively degrade proteins tagged with ubiquitin.

Once a Cell Enters Mitosis, the Molecules That Activate Division