Cell Cycle

Question 1

What are the three phases of interphase?

Answer 1

G1, S phase and G2

Question 2

What is the G1 phase?

Answer 2

It is an intermediate phase where normal function of the cell occurs

Question 3

What does the cell do in the G1 phase?

Answer 3

It makes sure that DNA can be replicated. It is where DNA is transcribed.

Question 4

What is the S phase?

Answer 4

The S phase is where DNA is replicated

Question 5

Why is it important to replicate DNA?

Answer 5

To allow each cell that is created to have the same genetic makeup

Question 6

Once DNA replication is over, how many chromosomes will be found during S phase?

Answer 6

There will be 2 copies of chromosomes. 42 mom, 42 dad.

Question 7

What else is replicated during the S phase?

Answer 7

Centrioles of the MTOC

Question 8

When in S phase, what form is DNA in?

Answer 8

All the DNA becomes euchromatic

Question 9

What is the purpose of the G2 phase?

Answer 9

It allows the cel to make sure it has all the right proteins for cell division

Question 10

What happens if a cell does not pass a checkpoint in the G1 or G2 phase?

Answer 10

The cell will undergo apoptosis

Question 11

Define: mitosis

Answer 11

The shorter phase of the cell cycle where the cell actually divides

Question 12

What are the two major phases of the cell cycle?

Answer 12

Interphase and mitotic phase

Question 13

Define: cell cycle

Answer 13

The two-phase cycle where a cell replicated it’s DNA, and then divides.

Question 14

Define: cyclin

Answer 14

A protein that constantly goes through synthesis and degradation during the cell cycle

Question 15

What happens when Cyclin is synthesized?

Answer 15

It activates CDK

Question 16

During which of the cell cycle does copying take place?

Answer 16

During interphase

Question 17

During which phase of he cell cycle does cleavage take place?

Answer 17

Mitosis

Question 18

What is the name of the phase between the end of M phase and the beginning of S phase?

Answer 18

G1

Question 19

What is the name of the phase between the end of S phase and beginning of M phase?

Answer 19

G2

Question 20

Through phosphorylation, what does the Cdks signal?

Answer 20

It signals that the cel is ready to move to the next stage of the cell cycle

Question 21

What does the cyclin-CDK complex do?

Answer 21

It acts as a signal to pass to the next cell cycle phase.

Question 22

When Cyclin degrades, what happens?

Answer 22

It deactivates the CDK to signal exit from a phase

Question 23

What is the name of the enzyme that digests Cyclin?

Answer 23

Cyclinase

Question 24

What happens when the MPF (Cyclin-CDK complex) phosphorylates p53?

Answer 24

It enters the cell and tries to repair the DNA

Question 25

What is another name for p53?

Answer 25

A tumor suppressant

Question 26

What happens if p53 doesn’t shut down? If it does shut down?

Answer 26

If p53 doesn’t shut down apoptosis occurs. if it does shut down, S phase continues

Question 27

_________ binds to Cdks to activate them. Once activated, Cdks signal progression through _____________.

Answer 27

Cyclin. Phosphorylation