Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Cell Biology > Chapter 18: The Cell Cycle > Flashcards

Chapter 18: The Cell Cycle Flashcards

You may prefer our related Brainscape-certified flashcards:
AP® Biology flashcards Biology 101 flashcards
1
Q

list 3 reasons why cell division is needed

A
  1. reproduction
  2. growth
  3. regeneration
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

unicellular organisms primarily use cell division for

A

reproduction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

in multicellular organism cell division is important in

A
  • growth
  • repair of tissues
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

what 4 events must occur for cell division?

A
  1. reproductive signal
  2. replication
  3. segragation
  4. cytokinesis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

the reproductive signal is necessary to

A

initiate cell division

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

replication refers to the

A

duplication of chromosomes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

segregation is the distribution of

A

replicated chromosomes to the 2 daughter cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

cytokinesis is the

A

separation of the 2 new cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

in prokaryotes binary fission results in

A

2 new cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

what are 2 external factors that initiate cell division?

A
  1. nutrient concentration
  2. environmental conditions
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

in bacteria what speeds up the division cycle?

A

abundant food supplies

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

in eukaryotic somatic cells each contain a

A

homologous pair of chromosomes

  • each parent contributes 1 homolog
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

for mammals all somatic cells possess

A

diploid (2n DNA)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

germ cells lead to the production of

A

gametes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

gametes ONLY contain

A

1 set of chromosomes (haploid= 1n)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

fertilization is when

A

2 haploid gametes fuse

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

fertilization leads to the formation of a

A

diploid zygote (2n)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

what are the 2 types of cell division in eukaryotes?

A
  1. mitosis
  2. meiosis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

in what cells does mitosis occur?

A

in somatic cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

in what cells does meiosis occur?

A

in germ cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

mitosis results in

A

2 identical sister cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

meiosis produces

A

4 haploid daughter cells different from each other and the parent

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

what are the 4 stages, in order, of the cell cycle?

A
  1. G1
  2. S
  3. G2
  4. M
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

what are examples of some things that are synthesized in the G2 phase?

A
  • signaling molecules
  • regulatory proteins
  • histone proteins
  • tubulin
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

during what stage of the cell cycle does reformation of the nuclear envelope occur?

A

cytokinesis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

reformation of the nuclear envelope allows for

A

uncoiling of the chromosomes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

what are the stages of mitosis?

A
  • interphase
  • prophase
  • prometaphase
  • metaphase
  • anaphase
  • telophase -> cytokinesis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

in early embryonic development cell division occurs but there is little

A

growth

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

what stage of the cell cycle is skipped during early embryonic development?

A

G1 & G2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

without G1 or G2 cells will continue to

A

decrease in size

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

for budding yeast what is the name of the regulatory check point?

A

START

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

What factors affect the START check point in yeast?

A
  • nutrient availability
  • mating factors
  • cell size
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

to maintain a constant size yeast cells must reach a minimum size to

A

pass START

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

what is the resting state for mammalian cells?

A

G0

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

what are the 4 cell cycle checkpoints

A
  1. DNA damage (G1)
  2. DNA damage (S)
  3. DNA damage (G2)
  4. spindle assembly (M)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

the G1 checkpoint checks for

A
  1. cell size
  2. nutrients
  3. GFs
  4. DNA damage
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

checkpoint for DNA damage in G1 is mediated by

A

p53

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

the S phase checkpoint includes coupling of the

A

S to G2 and M phase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

what is the licensing factor of the S phase checkpoint?

A

MCM helicase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

MCM helicase can only bind in

A

G1

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

the S phase checkpoint prevents DNA from being replicated more than once..how is this done?

A

by preventing the cells in G2 from reentering S phase

42
Q

when does the MCM helicase bind?

A

in the junction between G1 & S phase

43
Q

the G2 checkpoint of the cell cycle checks for

A
  • cell size
  • DNA replication
  • DNA damage
44
Q

the checkpoint for DNA damage in G2 is mediated by

A

Chk1 & Chk2

45
Q

the checkpoint during the M phase checks for

A
  • chromosome attachment to spindle
  • chromosome alignment
46
Q

what checkpoint occurs prior to anaphase?

A

the spindle assembly checkpoint

47
Q

when do the 2 resting states occur during the cell cycle?

A
  1. G1
  2. M
48
Q

progression of the cell cycle is regulated through

A
  • kinases
  • phosphatases
49
Q

kinases…

A

phosphorylates proteins

50
Q

phosphatases

A

dephosphorylates proteins

51
Q

what are the 3 key components of cell cycle regulation?

A
  1. maturation promoting factor (MPF)
  2. Cdc
  3. Cyclins
52
Q

MPFs were first studied in

A

frog oocytes

53
Q

in MPFs the transition from G2 to M is mediated by

A

Cdk1 & cyclin B

54
Q

CDK1 and cyclin B are together known as the

A

maturation promoting factor (MPF)

55
Q

Cdc was first studied in

A

yeast

56
Q

cdc stands for

A

cell division mutants

57
Q

the temperature sensitive mutants were found to undergo ___________ ____________ during specific points in the cell cycle.

A

growth arrest

58
Q

most Cdcs have been identified as

A

kinases called cyclin dependent kinases (Cdk)

59
Q

cyclins were discovered in what studies?

A

sea urchin

60
Q

during the sea urchin studies a series of proteins were identified to display a periodic pattern of

A

accumulation & degradation

61
Q

complexes of cyclin & Cdk trigger proteins at

A

checkpoints

62
Q

activation of Cdk-cyclin complexes requires

A

phosphorylation: kinases
dephosphorylation: phosphatases

63
Q

the Cdk/cyclin complex phosphorylates other ___________ which induces…

A
  • proteins
  • progression through the cycle
64
Q

what cdk/cyclin complex corresponds to the G1 phase?

A

Cdk4,6/CycD

65
Q

what cdk/cyclin complex corresponds to the G1-S phase?

A

Cdk2/CycE

66
Q

what cdk/cyclin complex corresponds to the S phase?

A

Cdk2/CycA

67
Q

what cdk/cyclin complex corresponds to the G2 phase?

A

Cdk1/CycB

68
Q

how are cyclins degraded?

A

by becoming ubiquitinated

69
Q

which cdk/cyclin complex is responsible for pushing cells past the G1 restriction point?

A

cdk4,6/cyclinD

70
Q

cdk4,6 is constitutively…

A

expressed

71
Q

cyclin D is synthesized in the presence of

A

GFs

72
Q

Rb physically inhibits

A

E2F

73
Q

E2F is the transcription factor that transcribes the next cyclin known as

A

cyclin E

74
Q

synthesis of cyclin D activates ___________ which phosphorylates _____. ____________ then promotes the transcription of _______________ ___.

A
  • Cdk4,6
  • Rb
  • E2F
  • cyclin E
75
Q

MCM can only bind in what phase of the cell cycle?

A

S phase

76
Q

what couples S phase to G2 phase?

A

Cdk2/cyclin E and MCM

77
Q

activated cdk2/cyclin E phosphorylates and activates

A

MCM

78
Q

what does MCM do to DNA?

A

denatures it for replication in the S phase

79
Q

Cdk 1 activation is through the phosphorylation of

A

threonine-161

80
Q

Cdk1 inhibition is through the phosphorylation of

A

Tyr15

81
Q

what is the MPF composed of

A

Cdk1/CyclinB

82
Q

MPF is inactivated by

A

cyclin B degradation

83
Q

what controls the timing of cell cycle events by inhibitory phosphorylation of Cdks?

A

wee1 kinases

84
Q

what removes inhibitory phosphates from Cdks?

A

Cdc25 phosphatase

85
Q

removal of inhibitory phosphates controls the

A

entry & progression of the cell cycle

86
Q

what are 4 functions of mitotic protein kinases?

A
  1. chromatin condensation
  2. nuclear envelope breakdown
  3. fragmentation of Golgi
  4. spindle formation
87
Q

what are the steps in the progression to anaphase?

A

MPF -> APC activation -> MPF Ubiquitination -> MPF degradation

88
Q

ubiquitination of securin causes an active ________ that leads to the degradation of ___________.

A
  • separase
  • cohesin
89
Q

what is a target of cyclin D/Cdk 4,6 that is often mutated in a wide array of human tumors?

A

RB

90
Q

Rb is the prototype of a tumor suppressor genes b/c its a gene whose

A

inactivation leads to tumor development

91
Q

the proteins encoded by tumor suppressor genes act as

A

brakes slowing down cell cycle progression

92
Q

GF signaling activates what pathway?

A

the Ras pathway

93
Q

Ras activation uses what cdk/cyclin complex?

A

Cdk4,6/Cyclin D

94
Q

an active Rb binds E2F transcription factor preventing

A
  • transcription of genes for DNA replication
  • passage through G1 into S phase
95
Q

when can Rb not bind to E2F?

A

when phosphorylated

96
Q

phosphorylated Rb cannot bind to E2F leading to

A
  • activation of gene transcription triggering onset of S phase
97
Q

when DNA damage is detected the cells arrest in _____ which activates _____ & ______these phosphorylate _____.

A
  • G1
  • ATM & Chk2
  • p53
98
Q

activated p53 causes transcription of ______. This inhibits the activity of _____________. what does this inhibit?

A
  • p21
  • Cdk2/cyclin E

inhibits:
- G1 to S transition
- replication

99
Q

in early G1 p27 inhibits

A

Cdk2/Cyclin E

100
Q

GF signaling causes the

A

degradation of p27 through phosphorylation

101
Q

in late G1 ___________ gets involved leading to…

A
  • MCM
  • DNA replication
102
Q

Chk1 and Chk2 are

A

inhibitors of cell cycle progression

Cell Biology (12 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions