Cell Cycle Flashcards
Interphase
The period between active cell division when cells increase their size and mass, replicate their DNA and carry out normal metabolic activities
Gap 1 (G1)
Actively dividing -very short
—organelle replicate eg mitochondria, Golgi
— transcription/ translation (protein synthesis)
—size of the cell increase
— replication
-respiration
S1
— chromosome replicates —> double stranded chromatids
—> DNA replication
Number of chromosomes doubles
G2 (gap 2)
- energy stores
- transcription/ translation
- chromosome repair
- size of cell increase
Mitosis
Nucleus is actively dividing
Cytokinesis
Cell division when new cells separate
G0
Control by checkpoints called cyclins , attach to enzymes called cyclin-dependent kinases (CDKs)
Animal cell cytokinesis
Ring of contractile fibre tighten around the Centre of the cell it forms a cleavage furrow. As it continues to contract the two cells have been separated
Plant cell cytokinesis
1) golgi apparatus secrete golgi vesicles
2) golgi vestibules move to towards the equator forming large vacuole
3) the vestibules enlarge and fuse together forming a cell plate
4) cell plate develops into a cell wall
Cycling
Cyclins(proteins) bind cyclin - dependant kinases these kinases (protein)
Then become active and attach the phosphate group to other proteins in the cell. This attachment of the phosphate triggers the other proteins to become active and carry out table specific to one of the phases of the cell cycle
Suggests how the cell cycle will be affect in that have become cancerous
-shorter growth or G phase / shorter interphase
Shorter cycle
Usual control/stops not working
Cells don’t become specialised
G0
Enter the G0 phase because the checkpoint didn’t pass
Differentiation
DNA damage
Senescent cells - Reached max No. of division
Role of the cell cycle
Asexual reproduction
Increase in cell number
Repair of tissue
Control of cell growth
G1 checkpoint
Cell size?
DNA damage?
G2
DNA replication
