LIFE 102 Lecture Notes - Lecture 28: Microtubule, Maturation Promoting Factor, Chromosome
Document Summary
Directs the sequential events of the cell cycle. The cell cycle stops until a go-ahead signal is received. *for many cells, the g1 checkpoint seems to be the most important one. *if a cell receives a go-ahead signal at the g1 checkpoint, it will usually complete the s, *if a cell does not receive the go-ahead signal, it will exit the cycle, switching into a nondividing state called the g0 phase. Cells will not begin anaphase until all chromosome are properly attached to the spindle at the metaphase plate. Assures that daughter cells have the correct number of chromosomes. Two types of regulatory proteins are involved in cell cycle control: A cyclin-cdk complex that triggers a cell"s passage past the g2 checkpoint into the. Kinetochores not attached to spindle microtubules send a molecular signal that delays anaphase. Proteins released by certain cells that stimulate other cells to divide. Stimulates the division of human fibroblast cells in culture.
