[名词解释] START (起点)

restriction point（限制点） S phase-promoting factor,SPF (S期促进因子) Cdc 28 protein (Cdc28蛋白) cyclin-dependent protein kinases, Cdks (周期蛋白依赖性蛋白激酶) anaphase-promoting complex,APC (后期促进复合物) START (起点)