LIFESCI 7B Chapter Notes - Chapter 16: Cytokinesis, Telophase, Brca1
10 Dec 2017
School
Department
Course
Professor
Document Summary
Interphase, cell has nuclear envelope and chromosomes are decondensed. Prophase, chromosomes condense and centrosomes migrate to opposite sides. Prometaphase, nuclear envelope breaks and microtubules attaches to chromosomes. Microtubules attaches to chromosomes at a site called kinetochores. Metaphase, chromosomes align in middle of cell. This is done by shortening of microtubules which happens at the kinetochore end, not at the centrosome end. Telophase, nuclear envelope reforms and chromosomes decondense. Cytokinesis, cell divides into 2 daughter cells. Kinases are proteins that phosphorylate other proteins. Cyclin-dependent kinases (cdks) are proteins that are activated by binding of cyclins. Cyclins are regulatory proteins, its levels rises and falls with each turn of cell cycle. Cyclins binds to cdks to form a cdk-cyclin complex. This activates the cdk which will then phosphorylate a target protein. The targeted proteins are often involved in promoting cell division. Different cdk-cyclin complexes regulate each stage of cell cycle.
