Control of cell cycle

Question 1

When is it vital that a cell divides?

Answer 1

• When its grown to right size
• Replicated DNA is error-free/repaired
• Chromosomes are in right positions during mitosis

Question 2

What does controlling all these factors ensure?

Answer 2

Ensures fidelity of mitosis - that 2 identical daughter cells are produced from parent cell

Question 3

What are checkpoints?

Answer 3

Control mechanisms of cell cycle

Question 4

What do checkpoints do?

Answer 4

Monitors + verifies whether processes at each stage of cell cycle has been completed before cell is allowed to progress to next stage

Question 5

What are the 3 checkpoints in the cell cycle?

Answer 5

G1 checkpoint, G2 checkpoint, spindle assembly checkpoint

Question 6

What is checked for in the G1 checkpoint?

Answer 6

Cell size, nutrients, growth factors, DNA damage

Question 7

What happens if the cell passes the G1 checkpoint?

Answer 7

Triggers cell to begin DNA replication. If it doesn’t pass, cell enters resting phase

Question 8

What is checked for in the G2 checkpoint?

Answer 8

Cell size, DNA replication, DNA damage

Question 9

What happens when cell passes G2 checkpoint?

Answer 9

Cell initiates processes that signal beginning of mitosis. If cell doesnt pass, put into resting phase

Question 10

Whats checked at the spindle assembly checkpoint?

Answer 10

Chromosome attachment to spindle

Question 11

What point of mitosis is cell at in spindle assembly checkpoint?

Answer 11

All chromosomes should be attached to spindles + have aligned

Mitosis cant proceed until spindle assembly checkpoint passed