Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

MCB 2 Block 4 > Cell Cycle > Flashcards

Cell Cycle Flashcards

1
Q

G1 info

A

Period respondent to mitogenic GFs and TGF-B

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

R point gen

A

In G1 and is point of no return

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

Interphase

A

Chromosome duplication and consists of G1, S, G2

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

Prophase

A

Chromo condensation

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

Prometaphase

A

Nuc envelope breakdown

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

Metaphase

A

Chromo align at metaphase plate

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

Anaphase A

A

Chromo movement to poles (Dyenin motor)

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

Anaphase B

A

Spindle pole seperation

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

Telophase

A

Nuc envelope reassemble

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

Cytokinesis

A

Contractile ring forms cleavage furrow

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

Restriction point

A

Related to presence or deprivation of mitogen. GFs coax G0 to G1. Commital step

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

G1

A

Synth mRNA and proteins, cell growth size

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

S

A

DNA replication- duplicate chromosomes, polyploidy same

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

G2

A

Cell growth

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

G1 to S

A

after R point. DNA dmg checkpoint for entrance to S

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

S phase check

A

DNA dmg checkpoint, halted if genome damaged

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

G2 to M

A

Entrance blocked if DNA rep not complete

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

M to Anaphase

A

inhibited if chromatids not assembled in mitotic spindles

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

G1 reg

A

CDK4,6/Cyclin D.

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

Inducer of S phase

A

SCF = ubiq-protein ligase

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

S phase role of cyclins

A

S phase cyclin-cdk induces DNA rep

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

G2 cyclin role

A

M cyclin-cdk induces early mitotic steps = cdk1/Cyclin B

23
Q

M phase reg

A

APC/C and Cdc14 phos = late mitosis

24
Q

Proteins that regulate cell cycle

A

Cyclins and CDK

25
Cyclins
regulate cdk activity. Levels are cyclic, rapidly synth and degraded. Bind to activated cdks
26
Cdk
Cyclin dependent kinases are proteins which phos other proteins. Dependent on cyclin binding for kinase activity. Constant lvls and act at checkpoints. After use, cyclin is degraded after detached.
27
G1 to R complex
Cyclin D-CDK 4,6
28
G1 to S complex
Cyclin E-cdk2
29
S to G2 complex
Cyclin A-cdk2
30
G2 to M complex
Cyclin B- cdk1
31
Draw G1 to S path
On paper
32
Cyclin D
Only in G1, rqrd for passage through R point. Made at start of G1 by GF, binds and activates CDK4/6. Degraded at end of G1
33
Cyclin E
Mid G1: CyclinD/cdk4,6 phos Rb releasing E2f - Cyclin E release and binding to cdk2.
34
DNA dmg and G1
Inhibit cyclin D first to stop progression past R point then Cyclin E
35
Normal G1
CyclinD/cdk4,6 phos Rb which breaks up pRb-E2F complex. E2F activates genes involved in S phase (DNA poly and cyclin E). CyclinE/Cdk 2 further activate Rb for more E2F (pos feedback)
36
Inhib cell cycle
Hypophos of Rb sequesters E2F TF therefore inhibiting cell progression
37
Cdk Inhibitors
INK4 (inhibs cdk4) binds and inhibs cyclinD/cdk4 = R point halt = p15 and p16 CIP (cdk inhib protein) family bind and inhibt all cyclin-cdk complexes = p21
38
TGF-B and cell cycle
Modulates levels of cdk inhibitors, strongly induces p15 (DNA dmg for p21). important for expression of p15 and p16 = pro-apop.
39
TGF-B pathway
TGF-B to TGFB2R dimerizes with and phosphorylates TGFB1 which phosphorylates SMAD2/3 which activate SMAD4 which goes to nuc and complexes with TFs leading to INKs p15 and p16 therefore preventing phos of Rb
40
HNPCC and TGF-B
slip and frameshift mutations assoc with TGFBR and assoc with loss of SMADs
41
Pancreatic carcinoma
loss of SMAD4 (loss of p15 and p16)
42
p53 general
kept at low levels by mdm2 (binds p53 in nucleus and ubiqs it). Excess mdm2 inhibits p53 and is often overexpressed in cancers. DNA dmg induces kinases which phos p53 (kinase = ATM) therefore blocking mdm2 binding therefore it is free from degradation leading to accumulation and transC of p21
43
ATM mutations
poor response to gamma radiation
44
p14ARF
tumor supp gene. Inhibits mdm2 and leads to p53 accumulation without need of phos. ARF sequesters mdm2 in nucleus. ARF responds to increased levels of E2F (ex: adenovirus, MYC, onceogenes, RAS)
45
Role of p53 and cancers
Inhibits oncogene induced transformations, inhbits tumor growth and progression, removes cells with DNA dmg, leads to apoptosis, transC BAX to BID (BAX needs to homodimerize to form pores [inhib by bcl-2= heterodimer] leading to cyt-C leak and apop).
46
G2 to M major
Cdk1/Cyclin B (M cyclin = MPF) enables G2 to M. Complex initially activated by phosphorylating CAK (cdk activating kinase). If DNA not completly replicated, signal sent to inhib cdk1/cyclin B.
47
Inhib of G2 to M
by Wee1 kinase stops MPF activation by another phos so it wins over CAK
48
Reg of G2 to M
Phosphatase Cdc25 activated by phos, removes Wee1 inhibiting phosphate therefore cyclinB/cdk1 active leading to nuc envelope breakdown, chromo condensation and bipolar spindle formation.
49
Nuc envelope breakdown
By lamin phosphorylation (MPF induces)
50
Anaphase promoting complex
M-cdk prepares duplicated chromosomes for separation: induce spindle form and chromo attach. APC induces chromatid separation at spindle attach checkpoint if everything is lined up.
51
APC activation
Activated by cdc20 and M-cdk. APC activates seperase which promotes progression into anaphase by seperating chromatids
52
Spindle attach checkpoint
Blocks metaphase-anaphase transition if kinetechores not properly aligned.
53
Kinetechore sensor
MAD2, activated if chromo not attached to spindle and division blocked at metaphase. Inhibits APC activation if not attached to kinetechore

MCB 2 Block 4 (10 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions