CAS BI 108 Chapter Notes - Chapter 11.2: Sister Chromatids, G1 Phase, G2 Phase

• School: Boston University
• Department: Biology
• Course: CAS BI 108
• Professor: Francis Monette

Document Summary

Cell cycle: the period from one cell division to the next; (1) interphase (2) mitosis (3) cytokinesis. Interphase: cell nucleus visible and typical cell functions occur, this includes dna replication. Cells spend most of their time in interphase. G1 phase: each chromosome is a single, unreplicated dna molecule w/associated proteins. Some cells remain in g1 for weeks/years. Special internal signals are then needed to prompt a cell to exit g0 and enter. G1-to-s transition: commitment made to dna replication and subsequent cell division. Each chromosome is duplicated now two sister chromatids. G2 phase: preparations for mitosis by synthesizing and assembling the structures that move the chromatids to opposite ends of the dividing cell. *the initiation, termination, and operations of these phases are regulated by specific signals. Specific internal signals trigger events in the cell cycle. Signals that control progress through the cell cycle act through protein kinases. Progress though the cell cycle depends on activities of cyclin-dependent kinases (cdk"s).