Lecture 13

Question 1

What is the C-value?

Answer 1

amount of DNA in pg per haploid (1n) genome

Question 1

What are the cell division phases?

Answer 1

M-phase, G1-phase, S-phase, G2-phase

Question 2

What happens during Interphase?

Answer 2

DNA replication 2C -> 4C

Question 3

What happens during M-phase?

Answer 3

Mitosis (nuclear divison) and Cytokinesis (cytoplasmic division)

Question 4

What happens to cells that are not dividing?

Answer 4

Go into G0 phase

Question 5

How are the phases in cell division called?

Answer 5

Interphase, Prophase, Metaphase, Anaphase, Telophase, Cytokinesis

Question 6

What are kinetochores?

Answer 6

Attatchment ankers for cell division microtubules

Question 7

What is closed mitosis?

Answer 7

Nuclear envelope stays intact during mitosis

Question 8

What is FACS sorting?

Answer 8

Sorting of cells according to cell cycle in a Flow cytometry machine
Normally ( a lot of cells in G1 lowest in S and middle in G2)

Question 9

How do you stop the cell cycle in yeast?

Answer 9

G1 phase: starvation
G2 phase: Nocodazole

Question 10

What is MPF and what does it do in the body?

Answer 10

MPF = CDK cyclins: controls the cell cycle and are contreolled by the ubiquitin degradation system

Question 11

How is Cdk regulated ?

Answer 11

By phosphorylation of Threonine

Question 12

How does Cdk actiavtion take place?

Answer 12

First cyclin binds to Cdk to make it partially active, then phosphorylation occures at the active site (Threonine residue) and Cdk becomes fully active: Kinase activates and phosphatase deactivates

Question 13

What happens if too little cdc ?

Answer 13

Elongated cell (increased G2)

Question 14

What happens if too much cdc?

Answer 14

Small cells (decreased G2)