7.1 Cell Cycle and Regulation

Question 1

cell cycle stages in order

Answer 1

Interphase (G1, S, G2), Mitosis
some cells go to G0 after G1

Question 2

interphase

Answer 2

the part of the cell cycle that isn’t Mitosis, includes G1, S, and G2

Question 3

G1

Answer 3

cell grows and prepares to replicate DNA

Question 4

G1 checkpoint

Answer 4

No DNA damage
sufficient resources

Question 5

G1 checkpoint proteins

Answer 5

stimulating: growth factor and G1-phase cyclin
inhibitory: p53 and retinoblastoma (Rb)

Question 6

S

Answer 6

cell replicates DNA

Question 7

S check point

Answer 7

No errors during DAN replication

Question 8

S check point proteins

Answer 8

stimulating: growth factors and S-phase cyclin
inhibitory: ataxia telengiectasia mutated (ATM) and breast cancer 1 (BRCA1)

Question 9

G2

Answer 9

cell continues to grow and prepares for division

Question 10

G2 check point

Answer 10

DNA without damage
chromosome set complete
enough cell components

Question 11

G2 check point proteins

Answer 11

stimulating: M-phase cyclin
inhibitory: p53

Question 12

Mitosis

Answer 12

cell division

Question 13

Mitosis check point

Answer 13

all sister chromatids attached to mitotic spindle

Question 14

Mitosis check point proteins

Answer 14

stimulating: anaphase-promoting compels/cyclosome (APC/C)
inhibitory: mitotic arrest deficient (MAD) proteins

Question 15

G0

Answer 15

cell goes here if it receives a signal to differentiate or if it lacks resources. differentiated cells stay in G0 permanently, but injured cells can re-enter the cell cycle

Question 16

stimulating proteins

Answer 16

stimulate cell cycle / “gas pedal”
examples: growth factor, cyclin, CDK

Question 17

inhibitory proteins

Answer 17

inhibit cell cycle / “break pedal”
example: p53

Question 18

proto-oncogenes

Answer 18

code for stimulating proteins (growth factors, cyclins)
become oncogenes when mutated
only need one oncogene to cause cancer

Question 19

tumor suppressor genes

Answer 19

code for inhibitory proteins (p53)
need both tumor suppressor genes mutated to cause cancer

Question 20

oncogenes

Answer 20

dominant allele / only need one to cause cancer
like a brick on the gas pedal
continues cell cycle when it shouldn’t

Question 21

mutated tumor suppressor genes

Answer 21

recessive allele / need both mutated to cause cancer
like a broken brake pedal
doesn’t stop cell cycle when it should