Cell Cycle

Question 1

What are the three cell cycle checkpoints?

Answer 1

1.) DNA damage 2.) replication of DNA 3.) reparation of sister chromatids

Question 2

G1 checkpoint

Answer 2

pass if DNA is undamaged, cell size is adequate

Question 3

G2 checkpoint

Answer 3

pass if chromosomes have replicated successfully

Question 4

M checkpoint

Answer 4

pass if chromosomes have attached to spindle apparatus

Question 5

DNA damage checkpoint (P53)

Answer 5

P53: senses DNA damage
-DNA damage activates protein kinases, kinases phosphorylate P53, phosphorylated P53 turns on gene expression of proteins that inhibit the cell cycle which gives time to repair damaged DNA

Question 6

What happens if there is too much DNA damage?

Answer 6

apoptosis or G0 (senescence: cells don’t divide)

Question 7

Describe the process of Bacterial Cell Replication

Answer 7

Binary Fission: DNA copied & protein filaments attach, DNA copies are separated, ring of proteins form, protein ring draws in membrane and spits cell into two cells