Roles of cyclins and CDKS on the cell cycle

Question 1

What are the two group of proteins responsible for promoting the cell cycle?

Answer 1

cyclins and cyclin-dependent kinases (Cdks),

Question 2

Cyclins regulate the cell cycle only when they are bound to

Answer 2

Cdks

Question 3

to be
fully active, the Cdk/cyclin complex must be

Answer 3

phosphorylated

Question 4

Cdk/cyclin complex being phosphorylated allows for the

Answer 4

phosphorylation other proteins that advance the cell cycle

Question 5

cyclins and cyclin-dependent kinases are ______modulators

Answer 5

positive

Question 6

Name the three negative modulators

Answer 6

(Rb, p53, and p21)

Question 7

(Rb, p53, and p21 act primarily at which checkpoint? What does this prevent?

Answer 7

G1 checkpoint.
-prevents the cell from moving forward to division until
damaged DNA is repaired

Question 8

What is the function of p53?

Answer 8

halts the cell cycle and recruits’ enzymes to repair damaged DNA; if DNA cannot be repaired, p53 triggers apoptosis to prevent duplication.

Question 9

What is the production of p21 triggered by and what is the function of P21?

Answer 9

triggered by p53; p21 halts the cycle by binding to and
inhibiting the activity of the Cdk/cyclin complex