BIO130H1 Lecture Notes - Lecture 25: Gene Duplication, G1 Phase, G2 Phase

• School: UTSG
• Department: Biology
• Course: BIO130H1
• Professor: Melody Neumann, Kenneth Yip

Document Summary

The cell cycle: m phase, the nucleus and cytoplasm divide, mitosis, cytokinesis. Interphase: period between cell divisions, g1 phase, normal metabolism, organelles duplicate, s phase, dna replication, chromosomal duplication, g2 phase, cell grows, cell prepares for mitosis. The cell cycle control system: delays later events until the earlier events are complete, the major checkpoints, start checkpoint, enter cell cycle and proceed to s phase. If environment is favorable, the checkpoint is passed. If environment is not favorable, the cell waits: g2 / m checkpoint, enter mitosis. Prophase: replicated chromosomes condense, mitotic spindle assembly starts and requires, centrosome duplication, bipolar spindle assembly. Chromosome condensation: at the end of g2 the replicated chromosomes are dispersed and tangled, at the beginning of mitosis chromosomes condense using condensin protein complex, the sister chromatids are resolved but remain associated, cohesin at the centromere. Centrosome duplication and mitotic spindle assembly: centrosome duplication starts in s phase, bipolar mitotic spindle assembly starts in m phase (prophase)