Cell Replication

Question 1

What stimuli does proliferation involve?

Answer 1

Physiologic OR pathologic

Question 2

What is proliferation controlled by?

Answer 2

Cell contact OR soluble signals

Question 3

How can cell proliferation be increased?

Answer 3

Shortening cell division cycle

Recruiting quiescent cells to divide + proliferate

Question 4

Describe labile cells

Answer 4

Constantly dividing

Regenerate quickly

Question 5

What is an example of labile cells?

Answer 5

Surface epithelium

Question 6

Describe stable cells

Answer 6

Low level of replication

BUT can divide in response to stimuli

Question 7

What is an example of stable cell?

Answer 7

Liver cells

Question 8

Describe non-dividing cells

Answer 8

Terminally differentiated

Unable to proliferate

Question 9

What is an example of non-dividing cells?

Answer 9

Neurons

Question 10

What would happen if you has increased CP?

Answer 10

Cancer

Question 11

What would happen if you had decreased CP?

Answer 11

Open wounds

Question 12

What are the parts of the cell cycle?

Answer 12

Interphase
Mitosis
Cytokinesis

Question 13

What is involved in interphase?

Answer 13

G1
S1
G2

Question 14

What is mitosis?

Answer 14

Nuclear division

Question 15

What is cytokinesis?

Answer 15

Cytoplasm division

Question 16

What do some cells enter?

Answer 16

G0

Question 17

Where do nerve cells go?

Answer 17

G0 permanently

Question 18

What happens in G1?

Answer 18

Before synthesis of DNA

Varies in length

Question 19

What happens in S1?

Answer 19

Nuclear DNA synthesised

Chromosomes duplicated

Question 20

What happens in G2?

Answer 20

After DNA synthesis complete

Lasts until mitosis

Question 21

What happens in G0?

Answer 21

Cell goes into non-dividing state
Doesn’t receive growth factor
Protect organism

Question 22

What are the stages of mitosis?

Answer 22

Prophase
Prometaphase
Metaphase
Anaphase
Telophase

Question 23

What happens in prophase?

Answer 23

Centrioles move to poles

Chromosomes condense

Question 24

What happens in prometaphase?

Answer 24

Microtubules attach to chromosomes

Question 25

What happens in metaphase?

Answer 25

Chromosomes align

Nuclei disappear

Question 26

What happens in anaphase?

Answer 26

Chromosomes divide

Move to poles (sister chromatids)

Question 27

What happens in telophase?

Answer 27

Nuclear membrane reappears

Chromosomes decondense

Question 28

What happens in cytokinesis?

Answer 28

Cytoplasm divides
Parent cell —-> 2 daughter cell
Identical genetic information

Question 29

What are the checkpoints?

Answer 29

G1
S1
G2
Mitosis

Question 30

What do they check at G1?

Answer 30

Damaged DNA?

Unfavourable environment?

Question 31

What do they check at S1?

Answer 31

Damaged or incomplete replicated DNA?

Question 32

What do they check at G2?

Answer 32

Damaged or incomplete replicated DNA?

Question 33

What do they check at mitosis?

Answer 33

Chromosome correctly attached to spindle fibres?

Question 34

What are CDK?

Answer 34

Enzymes that regulate cell cycle

Question 35

What are CDK activated by?

Answer 35

When cyclins bind

Question 36

When are CDK inactive?

Answer 36

Cyclin not bound

Question 37

What do CDK do?

Answer 37

Drive cell cycle

Question 38

Describe CDK regulation

Answer 38

Binding of cyclin changed tertiary structure of CDK
Exposes active site
Substrate + ATP bind to CDK
Substrate phosphorylated
Phosphorylated protein regulates cell cycle

Question 39

How can the cell cycle be manipulated?

Answer 39

Stop N2 getting to cell = no cell replication
Inhibit inhibitors = block signalling
Inhibit CDK = stop phosphorylation = stop progression from G1 —-> S1