Cell Cycle

Question 1

Stages of cell cycle

Answer 1

1. G1 - presynthetic growth
2. S - DNA synthesis
3. G2 - premitotic growth
4. M - mitosis
5. G0 - quiescent

Question 2

Activators of progression through cycle cycle?

Answer 2

Cyclins and cyclin dependent kinases (CDKs)

Question 3

Inhibitors of cell cycle?

Answer 3

Cyclin dependent kinase inhibitors (CDKIs)

Question 4

List the cyclins most important to cell cyle progression and where they act

Answer 4

D - G1/S, E - G1/S, A - S, B- G2/M

Question 5

Where is the cell cycle restriction point?

Answer 5

G1

Question 6

Where are the cell cycle checkpoints?

Answer 6

G1/S, G2/M

Question 7

What is the function of the G1/S checkpoint?

Answer 7

Ensure DNA is normal before it is replicated

Question 8

What is the function of the G2/M checkpoint?

Answer 8

Ensure DNA has been duplicated correctly before mitosis occurs

Question 9

Which CDK does cyclin D pair with?

Answer 9

4, 6

Question 10

Which CDK does cyclin E pair with?

Answer 10

2

Question 11

Which CDK does cyclin A pair with?

Answer 11

2, 1

Question 12

Which CDK does cyclin B pair with?

Answer 12

1

Question 13

What are the INK4 family of proteins and what is their function?

Answer 13

p15, p16, p18 and p19. Inhibit cyclin D/CDK4 complex

Question 14

What is p21?

Answer 14

A CDKI.

Question 15

What are the other members of the p21 CDKI family?

Answer 15

p27 and p57

Question 16

Which cylin/CKD complexes do p21, p27 and p57 inhibit?

Answer 16

D/4, D/6 and E/2

Question 17

What is the role of cyclin D/CKD 4, D/6 and E/2?

Answer 17

Phosphorylate retinoblastoma (Rb) protein, enabling progression through G1/S checkpoint.