Brainscape's Knowledge GenomeTM

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


See full index

MFoM > 04a: Cell Cycle and Apoptosis > Flashcards

04a: Cell Cycle and Apoptosis Flashcards

1
Q

Give examples of adult cells that don’t undergo proliferation.

A

Nerve, striated muscle, cardiomyocytes

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

Give examples of adult cells that undergo frequent proliferation.

A

Fibroblasts, Bone marrow, Myeloid

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

A non-dividing cell is in (X) phase.

A

X = Go

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

Following the appropriate stimulus, cell enters cycle of division and proceeds through which phases (in order).

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

Cell undergoes (X) in G1.

A

X = Growth and metabolism

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

Cell undergoes (X) in S.

A

X = DNA replication

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

Cell undergoes (X) in G2.

A

X = Preparation for division

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

Chromosome number in G1.

A

2n (diploid)

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

Chromosome number in S.

A

2n to 4n

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

Chromosome number in G2.

A

4n

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Chromosome number in M.

A

4n to 2n

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

Condensing chromosomes indicate (interphase/prophase).

A

Prophase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Anaphase in mitosis involves separation of:

A

two sister chromatids

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

Give examples of cells that skip certain cell cycle phases. Which phase(s) does each skip?

A
  1. Megakaryocyte (late anaphase and cytokinesis)

2. Trophoblast (late anaphase and cytokinesis)

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

(X) cells have abnormal, uneven segregation of chromosomes, resulting in (haploid, polyploid, uneuploid) cells.

A

X = cancer

Uneuploid

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

Disease associated with (X) cause reduction in reduced platelet counts?

A

X = decreased polyploidy in megakaryocytes

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

Cyclin D peaks primarily in which phase?

A

G1

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

Cyclin E peaks primarily in which phase?

A

S

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

Cyclin A peaks primarily in which phase?

A

S (and a bit into G2)

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

Cyclin B peaks primarily in which phase?

A

Late G2, and into M

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

Which proteins are important for entrance/transitions into/out of cell cycle phases?

A

Cyclins

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

Cyclin forms an active complex when coupled with:

A

CDK (cyclin-dependent kinase)

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

What are CKIs? List examples.

A

CDK inhibitors

p16, p21, p27

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

CKIs inhibit which specific reaction?

A

Phosphorylation by active Cyclin-CDK complex

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

High levels p16 effect on cell cycle.

A

Inhibits Cyclin D (coupled with CDK 4 or 6); so stops cell from entering G1 phase

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

High levels of p21 effect on cell cycle.

A

Inhibits Cyclin E (coupled with CDK 2); halts cycle

27
Q

High levels of p27 effect on cell cycle.

A

Inhibits Cyclin E or A (coupled with CDK 2); halts cycle

28
Q

Whats the function of the CDC2-Cyclin B complex?

A

Activates proteins on the chromosomes that are responsible for chromosome segregation.

29
Q

What’s the primary control mechanism for CKIs?

A

Transcription regulation

30
Q

Rb is known as a(n):

A

Tumor suppressor

31
Q

Free E2F function:

A

Activates genes that regulate DNA synthesis

32
Q

E2F, bound to (X), function:

A

X = Rb

Function (activates genes for DNA synthesis) is suppressed

33
Q

CDK-cyclins affect (Rb/E2F) in which way(s)?

A

Affect both! Directly phosphorylate Rb, so can’t bind E2F. This allows E2F to carry out function of gene activation (cell cycle proceeds)

34
Q

CKI affect (Rb/E2F) in which way(s)?

A

Indirectly allow cell cycle arrest by inhibiting Cyclin-CDK complex from phosphorylating Rb.

35
Q

Necrotic cell death involves (X) and occurs as result of (Y).

A

X = lysis of membrane and release of cell content

Y = trauma or infection

36
Q

Apoptosis is result of (X) activation by (Y) signals.

A 
X = caspases
Y = intracellular biochemical signals
37
Q

Caspases are specifically (X) enzymes, so they act to:

A

X = cysteine protease

Hydrolyze specific peptide bonds

38
Q

Caspases are initially produced as:

A

Inactive pro-caspases

39
Q

What initial step allows activation of the caspase cascade?

A

Pro-caspases (8, 9, 10) are autocatalytic, so cleave themselves to produce active caspases

40
Q

Active caspases 8-10 act on:

A

Caspases 3, 6, 7 (cleave them)

41
Q

Active Caspases 3, 6, 7 act on:

A

Other cellular proteins

42
Q

An apoptotic cell undergoes changes in which structure(s)?

A
  1. Plasma membrane
  2. Cytoskeleton
  3. Nuclear DNA (fragmentation)
43
Q

In apoptotic cell, degradation of chromosomal DNA is carried out by:

A

Endonucleases (caspase-activated DNase)

44
Q

Fate of remains of apoptotic cell

A

Uptaken and digested by macrophages

45
Q

What are the main pathways to apoptosis?

A
  1. Death receptor pathway

2. Mitochondrial pathway

46
Q

Whats TNF-a?

A

Death ligand that, upon binding death receptor, initiates apoptosis via death receptor path

47
Q

List steps that initiate death receptor pathway.

A
  1. TNF-a binds Fas death receptor
  2. Intracellular adaptor protein (FADD) binds to cytoplasmic side of death receptor
  3. Recruits pro-caspase (8-10), which undergo autocatalytic activity and initiate caspase cascade
48
Q

Under normal conditions, cytochrome C is present in/on:

A

In mitochondrial intermembrane space

49
Q

Under apoptotic conditions, cytochrome C is present in/on:

A

Translocated to cytosol via pores

50
Q

Upon leaving mitochondria, cytochrome c:

A

Binds Apaf1 and pro-caspase 9, forming apoptosome

51
Q

What’s the apoptosome?

A

Complex of:

  1. Cytochrome c
  2. Apaf1
  3. Pro-caspase 9
52
Q

What regulates Cytochrome C release from mitochondrion?

A

Channels (Bcl proteins)

53
Q

Bcl proteins are divided into (X). List examples of each.

A

X =

  1. Anti-apoptotic: Bcl-2 and Bcl XL
  2. Pro-apoptotic: Bax and Bak
54
Q

Bcl-2 activity has what effect on Cytochrome C movement?

A

Prevent formation of membrane pores through which Cytochrome C would leave mitochondria

55
Q

The mitochondrial membrane pores are composed of:

A

Dimers or polymers of Bax and Bak

56
Q

List some facilitators of Bax and Bak. What effect do these have on apoptosis?

A

Bid, Bad, Noxa

Promote apoptosis

57
Q

T/F: the presence of Bax/Bak facilitators determines cell death or survival.

A

False - ratio between anti- and pro- apoptotic proteins is determinant of cell death/survival

58
Q

XIAP is (X) with affinity for (Y).

A

X = caspase inhibitor protein

Y = active caspases

59
Q

What’s the Smac-DIABLO pathway?

A

Apoptotic pathway in which Smac/DIABLO protein inhibits apoptotic/caspase inhibitor XIAP

60
Q

The p53 protein is an example of a(n) (X) that acts by affecting:

A

X = tumor suppressor

Transcription (regulates expression of various genes)

61
Q

How does p53 (prevent/induce) apoptosis?

A

Induces

  1. Increases transcription of Bax and Noxa
  2. Activates cytoplasmic Bax to bind mitochondrial membrane
  3. Increases p21 expression (cell cycle arrest)
62
Q

Raf, a(n) (X) protein, (prevents/induces) apoptosis by:

A

X = MAP kinase

Prevents;

Phosphorylates Bad, leading it to dissociate from mitochondrial membrane

63
Q

One way to prevent apoptosis is (X) of Bad, causing its (increased/decreased) enhancing action on (Y). Name some enzymes that have this function.

A

X = Phosphorylation

Decreased

Y = Bax and Bcl-XL

Raf and Akt

MFoM (20 decks)

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