BSI Lecture 20 Cell Cycle Flashcards
How does APC trigger anaphase?
Ubiquitilate of securin
How does activation of the APC complex lead to separation of the sister chromatids?
The APC complex causes ubiquitylation and degradation of securin, activating ubiquitin separase, which separates the chromatids
DNA Replication; what are the 3 steps?
1) Unzipping
2) Complementary base pairing
3) Sugar-phosphate backbone formed connecting nucleotides in the 2 new strands
Segregation of the sets of chromosomes to opposite ends of the spindle occur in which phase?
Anaphase
Nucleus expands and chromosomes decondense to interphase state, what phase does this occur in?
Telophase
Assembly of contractile ring necessary for cytokinesis occurs in which phase?
Telophase
Which enzyme replicates DNA?
DNA Polymerase
What are the phases of mitosis?
Prophase Prometaphase Metaphase Anaphase Telophase
What are the two general phases of the cell cycle?
Interphase and M-phase
Interphase consists of which phases?
G1, S, G2
Where on the chromosomes are kinetochores located?
On the centromeres of sister chromatids
What is cytokinesis?
Division of cytoplasm (including all organelles) by the contractile ring which pinches the two daughter cells part.
How is APC activated?
M-Cdk phosphorylates APC, then Cdc20 binds to APC, activating it.
Give two examples of cell types that remain in G0 permanently?
Differentiated nerve and muscle cells.
Replicated chromosomes condenses in what phase?
Prophase
T or F? The nuclear envelope is still intact during prophase.
True
Nuclear envelope breaks down during which phase?
Prometaphase
_______ are protein complexes which assemble on the condensed chromosomes.
Kinetochores