AP BIOLOGY

Detailed explanation-1: -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: -In addition to driving the events of M phase, MPF also triggers its own destruction by activating the anaphase-promoting complex/cyclosome (APC/C), a protein complex that causes M cyclins to be destroyed starting in anaphase.

Detailed explanation-3: -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-4: -CDK1 is a crucial regulator of mitotic transition and its activation drives entry into mitosis [4, 5]. MPF activity must be sustained from prophase to metaphase and subsequently turned off when cells enter anaphase.

Detailed explanation-5: -The activation of MPF is the key that catalyzes the end of meiotic arrest in diplotene and the continuation of meiosis though metaphase I, anaphase I, and telophase I (division of the primary oocyte, forming a secondary oocyte and the first polar body) until metaphase II of meiosis, when a second meiotic arrest occurs.