5.7. M to G1 transition :
After the completion of mitosis, the entry into another round of mitosis is prevented by inhibiting Cdk activity. During the transition from metaphase to anaphase, Cdh1 is phosphorylated by M-Cdk and thus prevent it from attaching to APC/C. As the M-Cdk is degraded in later stage of mitosis, cdc20 gets released and Cdh1 can bind to APC/C, thus keeping it activated for the M/ G1transition. Cdh1 is necessary for APC to degrade the Cyclin B. Degradation of Cyclin B is mark of exit of Mitosis.