BI236 Lecture Notes - Lecture 19: Metaphase, Dna Replication, G1 Phase
Document Summary
Lecture 19 march 1st 2017 6:1 the cell cycle, part 2. At each of these points conditions within the cell determine whether the cell will proceed to the next stage of the cycle. Three transition points: late g1, g2-m transition, metaphase anaphase transition. Non dividing cells exit cycle in late g1 or g2: restriction point in late g1. G1 phase: varies among cell types. In cultured cells, can stop or slow down the process of cell division: by allowing the cells to run out of either nutrients or space or, by adding inhibitors of vital processes such as protein synthesis. Then the cell cycle is halted at g1. The ability to pass though the restriction point is influenced by the presence of extracellular growth factors (proteins that stimulate (or inhibit) cell proliferation) Cells that successfully pass through are committed to s.
