cell cycle Flashcards
the eukaryotic cell cycle is divided into
4 phases: G1, S, G2, M
When in mitosis does DNA replication occur?
S phase
what form is DNA in in interphase?
chromatin (mixture of DNA and proteins that form the chromosomes)
what is the kinetochore
protein structure on chromatid where the microtubules attach
what do plants have to assist in cytokensis and what do they do?
cell plates which grows outwards from centre of the cell to help them separate
what is cell plate made up of?
plasma membranes and cell wall components delivered by vesicles
spindle assembly checkpoint at m to a checkpoint ensures
spindle fibre is attached properly to chromatid
what does BrdU do?
incorporates into the growing strand during the S phase (can do this coz it mimics thymidine)
flow cytometry of proliferating cells show
DNA content of cells at different stages of the cell cycle
what are cyclins?
proteins that control the progression of cell cycle
cdks are present at xxx but xxx
constant levels but must be activated to work
what does phosphorylation do?
changes the structural conformation of a protein, causing it to become either activated or deactivated thus modifying its function
what do cdks do?
phosphorylate proteins involved in cell cycle regulation
eg ones that control chromosome condensation
how is cdk2 activated?(t loop)
cyclin binds to it and moves the T loop away from active site and partially activates cdk2
then CAK phosphorylates an amino acid n on the Cdk active site causing conformational change
what are cdks activated by
cyclins
