PATHOLOGY

Detailed explanation-1: -○ The cyclin level rises during the S and G2 phases and then falls abruptly during M phase. MPF (“maturation-promoting factor” or “M-phase-promoting factor”) triggers the cell’s passage past the G2 checkpoint to the M phase. ○ MPF promotes mitosis by phosphorylating a variety of other protein kinases.

Detailed explanation-2: -It stimulates the mitotic and meiotic phases of the cell cycle. MPF promotes the entrance into mitosis (the M phase) from the G2 phase by phosphorylating multiple proteins needed during mitosis. MPF is activated at the end of G2 by a phosphatase, which removes an inhibitory phosphate group added earlier.

Detailed explanation-3: -How does MPF allow a cell to pass the G2 phase checkpoint and enter mitosis? A sufficient amount of MPF has to exist for the cell to pass the G2 checkpoint; this occurs through the accumulation of cyclin proteins which combine with Cdk to form MPF.

Detailed explanation-4: -Maturation promoting factor (MPF) is a cell cycle checkpoint that regulates the passage of a cell from the G2 growth phase to the M phase. It is also known as the G2 checkpoint, and ensures that DNA replication during the S phase did not produce any mistakes.

Detailed explanation-5: -DNA damage. DNA replication completeness.