Topic H Flashcards
(95 cards)
1
Q
Interphase
A
- organelles double in number/volume
- DNA and centrosome rep.
- cell elongates (plant cells)
2
Q
Prophase
A
- Centrosomes move to poles
- chromosomes condense
3
Q
Prometaphase
A
- Nuclear envelope dismantels
- MT connect to targets
4
Q
Metaphase
A
- chromosomes move to middle
5
Q
Anaphase
A
- Chromatids separate
- chromosomes move to poles
- cell elongates (animal cells)
6
Q
Telophase
A
- chromosomes de condence
- nuclear envelope reforms
7
Q
Cytokinesis (animals)
A
- contractile ring
8
Q
Cytokinesis (plant cells)
A
- vesicles containing cellulose fuce to make cell wall
9
Q
Chromosome proteins
A
- Histones
- Cohesins
- Condensins
- Kinetochore
10
Q
Histones
A
- balls of 8 little proteins
- compact DNA
- When: Always
- where: Everywhere
11
Q
Cohesins
A
- Large heteotrimer rings
- 3 polypeptides
- proteins that load onto DNA in G1
- old sister chromatids together –> need to be put on before DNA replication (Replication Fork pass through the ring during DNA replication)
- When: G1 –> anaphase
- where: centromeres
12
Q
Condensins
A
- hold and connect DNA
- Similar to Cohesins
- when: Prophase –> telophase
- where: Everywhere
13
Q
Condensins proteins are added during _____
A
Prophase
14
Q
Kinetochore proteins
A
- connect MT to centromere region of DNA
- When: metaphase –> prophase
- where: Centromere
15
Q
Cellulose
A
- polysaccaride
- cell wall
- beta glucose monomer
16
Q
Plant cells in a ___ Environment
A
Hypotonic
17
Q
Cells ____ before mitosis
A
elongate
18
Q
Intermediate filaments during:
interphase
A
interphase: nuclear lamina
19
Q
Intermediate filaments during: Prometaphase
A
Prometaphase: nuclear lamina are temporarily deactivated (break into parts)
20
Q
Intermediate filaments during: Telophase
A
nuclear lamina are re-activated (reassembles around chrom. resealing nuclear environment)
21
Q
Microtubules: prometaphase (3)
A
Aster MTs
Kinetochore MTs
Interpolar MTs
22
Q
Aster MTs
A
inner surface of plasma membrane
Anchors Centersomes
makes sure its stationary
23
Q
Kinetochore MTs
A
kinetochore proteins at centromere DNA
Move Chrom. to middle of cell during metaphase
24
Q
Interpolar MTs
A
Mts from opposite poles
Elongate cells
Cytokinesis (plant and animal cells)
25
MT during metaphase
MT search for and capture Chromo.
| Only attach when it can withstand pulling forces are stabilized
26
MT during Anaphase
kinetochore MT disassemble
27
T/F
| Aster MT stop centrosomes from being pulled into middle of cell
T
28
____ MT form extension bundles and elongate cell
Interpolar MT
29
Kinetochore MTs are ___ end directed & ___ motor proteins
Plus; kinesin
30
Anaphase A
Chromosomes pulled towards centrosomes
31
Anaphase B
Centrosomes move apart
32
MT during cytokinesis in plant cells, ____ move into middle of the cell on ___ MTs
Vesicles contain cellulose; Interpolar
33
What happens with Actin Filaments during cytokinesis in animal cells
ring forms close to Interpolar MTs
34
The Cell cycle is regulated by what 4 protein complexes
G1-Cdk
S-Cdk
M-CdK
APC
35
G1-Cdk
```
G1-Cdk = G1-Cyclin + Cdk
Mechanism: phosphorylation
# of targets: 2
prep for DNA rep.
G1 checkpoint --> near end of G1
```
36
S-Cdk
```
S-Cdk = S-Cyclin + Cdk
Mechanism: phosphorylation
# of targets: 2
Start DNA rep (sphase)
G1 --> S phase
```
37
M-CdK
```
M-CdK = M-Cyclin + Cdk
Mechanism: phosphorylation
# of targets: 6
Starts prophase (mitosis)
G2 checkpoint -- G2 --> prophase
```
38
APC
Anaphase promoting complex
starts anaphase
Mechanism: attach ubiquitin proteins to target protein
# of targets: 2
M checkpoint -- Metaphase ---> anaphases
39
Cyclin Cdks are regulated by...(3)
availability of cyclins
phosphorylation
inhibitor proteins
40
What do kinases do?
Phosphorylate target proteins (turn on)
41
Cdk
Cyclin dependent kinases (Cdks)
| act during cell cycle
42
Cyclins
activate Cdks and dictate their target
43
Cdk are activated by ____
Cyclins
44
Cdk are activated AND inhibited by ____
phosphorylation
45
Cdk are activated AND inhibited by ____
phosphorylation
46
Polyubiquinated protiens are broken down by ____
Proteasomes
47
Polyubiquinated proteins are broken down by ____
Proteasomes
48
When does G1-Cdk become activated and inactivated?
Addition of Phosphate/ removal of phosphate
49
When does S-Cdk become activated and inactivated?
Addition of Phosphate/ removal of phosphate
50
When does M-Cdk become activated and inactivated?
Addition of Phosphate/ removal of phosphate
51
When does APC become activated and inactivated?
Addition of Ubiquitin protein / removal of Ubiquitin protein
52
___ indirectly activates Transcription factors
G1-Cdk
53
cell receives a signal then ___
G1 cyclin synthesized turning on G1-Cdk
54
G1-Cdk activating Transcription factors mechanism?
: G1-Cdk inactivates the inhibitory Rb proteins
55
Oris
Origin of replication
| Where DNA rep starts (rep. fork)
56
____ indirectly actiavtes S-Cdk
G1-Cdk
57
ORC (origin recognition complex) and helicases put onto oris during ___
G1
58
Oris fire once at the start of ____
s Phase
59
S-Cdk triggers ___
s Phase
60
Oris can't fire a second time (T/F), explain.
T --> once/ cell cycle
ORCs phosphorylated Therefore inactive till next cell cycle
not enough helicases available
61
___ indirectly activates the centrosomes for centrosome duplication/rep
S-Cdk
62
Mitosis is use to rep. the nucleus (T/F)
T
| 1 per cell --> 2 per cell
63
___ is activated when DNA rep. and repair are complete
M-Cdk
64
___ prevents activation of M-Cdk
ssDNA
65
if M-Cdk is actived then ____
the cell is ready to finish interphase and do mitosis
66
An ___ phosphate is removed by a ___ to activate Mcdk
inhibiting; phosphatase
67
____ activates MT regulatory proteins
M-CdK
68
____ inactivates Nuclear lamins and dismantles ____; during ___
M-Cdk; nuclear envelope; prometaphase
69
____ inactivates Nuclear pore proteins
M-Cdk
70
____ activates condensin proteins
M-Cdk
71
What stops during mitosis and why
DNA repair and RNA synthesis; must all stop since chrom condensed
72
Myosin are temporarily inactivated by what?
inhibitory phosphate
73
___ activated by M-CdK
APC
74
____ inactivated by unattached chromosomes
APC
75
___ indirectly destroys Cohesins
APC
76
Steps for APC indirectly destroys Cohesins
1. APC destroys securin (which then activates separase)
| 2. separase destroys cohesins by proteolysis
77
___ destroys M-Cdk
APC
78
what changes caused by M-Cdk are reversed?
MT return to interphase behavious
Nuclear pores and Lamina reform
Chromosomes decondense (Membrane and chrom fuse to become 1 nucleus)
APC inactivates
79
Each chrom. gets a coating of _____ and _______ ad it expands
Nuclear lamins; ER membrane
80
Why is the membrane coat tight
to exclude cytosolic proteins
81
Cytokinesis in animials cells is done by what
actin filaments + Myosin
82
Cytokinesis in animials cells steps
1. inhibitoy phosphates are removed
2. contraction bundels contract
3. squeezing the middle making 2 cells
83
In G1 all regulatory proteins are _____
inactive
84
G1-Cdk is activated by ____ in unicellular Euk and ___ in multicellular Euk.
large cell volume; mitogens
85
G1-Cdk, S-Cdk, and M-Cdk are inhibited by ___ so that the cell cycle pauses while the ___
DNA damage; DNA is repaired
86
M-Cdk is inhibited by ____ to prevent prophase starting before S phase is complete
incompletely replicated chromosomes
87
APC is inhibited by ____ to prevent anaphase from starting before metaphase is complete
unattached chromosomes
88
steps of repairing blood vessel damage
blood vessel damage --> Platelet cell -->PDGF --> Fibroblast reproduction --> collagen
89
to make collagen what signal is needed
paracrine
90
What happeneds if the DNA is damaged
all euk cells stop cell cycle
| inhibition of G1Cdk SCdk and MCdk
91
p53
53 kDa protein
+ transcription factor
regulated at the level of
92
p53
53 kDa protein
+ transcription factor
regulated at the level of protein stability
93
___ indirectly stops cell cycle. process?
p53
| moderate dna damge --> p53 turns on p21 gene (Cdk inhibitor protien)
94
___ indirectly fixed DNA damage. process?
p53
| moderate dna damge --> p53 turns on DNA repair Enzyme genes
95
p53
53 kDa protein
(+) transcription factor
regulated at the level of protein stability
