Once a cell completes mitosis, molecular division triggers must be turned off. What happens to MPF during mitosis?
A) Cyclin is degraded; the concentration of cyclin- dependent kinase remains unchanged, but without cyclin, MPF is not formed.
B) The cyclin- dependent kinases take on a function unrelated to mitosis.
C) It is completely degraded.
D) Cyclin- dependent kinase is degraded; cyclin concentration remains constant, but without cyclin- dependent kinase, MPF is not formed.

Question

Quizplus · Accepted Answer

During mitosis, cyclin-dependent kinase (CDK) combines with cyclin to form the mitosis-promoting factor (MPF). Once mitosis is complete, cyclin is degraded, causing the concentration of CDK to remain unchanged, but without cyclin, MPF cannot form. This results in the turning off of molecular division triggers, including MPF.

Once a Cell Completes Mitosis, Molecular Division Triggers Must Be