Brainscape's Knowledge GenomeTM

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


See full index

Biochem 1 (WPH) > Membranes, Organells, Cytoskeleton - Symes > Flashcards

Membranes, Organells, Cytoskeleton - Symes Flashcards

1
Q

__ are the site of intracellular degredation

A

lysosomes

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

are lysosomes acidic or basic?

A

acidic

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

T/F the endomembrane system includes all of the following:

  • plasma membrane
  • ER
  • golgi
  • lysosomes
  • nuclear envelope
A

true

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

neucleoulus is the site of..

A

rRNA transcription
ribosome assembly
telomerase assembly

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

T/F the ER and golgi are continuous with the outer nuclear membrane

A

true

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

in the lysosome:
proteases degrade …
nucleases degrade …
other enzymes degrade…

A

proteins
RNA and DNA
polysaccharides and lipids

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

microfilaments are made of…

A

actin

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

mircotubules are made of…

A

tubulin

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

intermediate filaments are made of…

A

multiple proteins including vimentin, desmin, keratin, and neurofilaments

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

vimentin, desmin, keratin, and neurofilaments are all subunit proteins of…

A

microfilaments

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

what are 3 ways lipids can move in a membrane

A

laterally
rotationally
trans (flip-flop)

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

glycerophospholipids, sphingolipids, and cholesterol compose…

A

the 3 major lipids of biological membranes

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

what is the structure of a glycerophospholipid

A

polar head connected to one saturated and one unsaturated fatty tail through a phosphate and a glycerol group

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

describe heredetery sphyrocytosis

A

in the RBC:

  • spectin proteins form a stuctural latticework along membrane surface
  • ankyrin and band 4.1 adaptor proteins connect spectrin lattice to membrane at band 3 integral membrane proteins
  • defects in any of these proteins can cause spherical cells instead of biconcave cells
  • sphericytes cannot squeeze through capillaries and lose membrane and lyse
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what are 4 proteins that, if mutated and defective, can cause hereditary spherocytosis

A

spectrin - lattice work along RBC membrane
ankyrin - connects spectrin to band 3
band 4.1 - connects spectrin to band 3
band 3 - integral membrane protein

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

in a membrane, what is a:
surface protein
peripheral protein
integral protein

A

surface protein - on outer surface
peripheral protein - associated with one side
integral protein - spans whole membrane

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

what is normal physiolgical temp in C and F

A

37 C

98.6 F

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

what is pneumonia and what does it look like on chest xray

A
  • lung infection

- hazy area

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

how are sphingolipids different from gycerophospholipids

A

derived from sphingosine not glycerol

otherwise similar

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

failure to dispose of what type of membrane lipid most commonly results in lysosomal storage disease?

A

sphingolipids

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

a cherry-red spot in the retina is caused by what disease?

A

Tay-Sachs disease

lysosomal storage disease

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q 
Tay-Sachs disease
Fabray's disease
Gaucher disease
Niemann-Pick disease
GM1 gangliosidosis
are all what kind of disease?
A

lysosomal storage disease
(all due to mutations in sphingolipase enzymes – and Niemann-Pick may also be caued by mutations in lysosomal cholesterol transporters)

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

Tay-Sachs disease is caused by

A

a mutation in a lysosomal enzyme that normally breaks down sphingolipids

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

Fabry’s disease is caused by

A

a mutation in a lysosomal enzyme that normally breaks down sphingolipids

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

Gaucher disease is caused by

A

a mutation in a lysosomal enzyme that normally breaks down sphingolipids

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

Niemann-Pick disease is caused by

A

mutations lysosomal cholesterol transporters and enzymes that normally breaks down sphingolipids

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

GM1 gangiosidosis is caused by

A

a mutation in a lysosomal enzyme that normally breaks down sphingolipids

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

describe atypical pneumonia

A
  • caused by inhaled bacteria
  • extracts cholesterol from mucus membranes
  • causes cilia to go limp (not beat)
  • muchus accumulation for richer bacterial medium
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

most transmembrane proteins are glycosylated on the __ side of the plasma membrane

A

non-cytosolic side

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

T/F carbohydrates on the lipid membrane play roles in cell-cell recognition, adhesion, and receptor function

A

true

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

what are liposomes

A

bilayered vesicles often used for drug delivery

  • can make temperature sensitive to target
  • can attach antibodies to target
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

2 ways to target liposomes for drug delivery

A
  • make temperature sensitive so release contents at site of inflammation or cancer
  • attach antibodies to target to particular antigen
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

how is membrane fluidity affected by temp increase

A

more fluid (more kinetic energy)

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

how is membrane fluidity affected by fatty acid chain length

A

less fluid (more hydrophobic interactions)

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

how is membrane fluidity affected by more unsaturation

A

more fluid (cannot pack together so well)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

how is membrane fluidity affected by more cholesterol

A

less fluid (usually)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

cystic fibrosis is caused by a defect in what protein?

A

ABC ATPase pump for Cl-

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

describe hutchison Gilfor progeria syndrom

A

defect in nuclear laminin causes disruption of shape, function, mitosis, etc cell death

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

T/F the nuclear envelope is made of a lipid bilayer

A

false - made of 2 lipid bilayers

inner and outer nuclear membranes

40
Q

is the nuclear lamina associated with the inner or outer nuclear membrane?

A

inner

41
Q

T/F the outer nuclear membrane is continuous with the ER

A

true

42
Q

what is the nuclear matrix?

A

a complex of fibrillous proteins thought to be the site of RNA processing

43
Q

what is the nuclear lamina?

A

a thick layer of fibrous proteins associated with inner nuclear membrane, composed of intermediate filaments

44
Q

what type of cytoskeletal elements form the nuclear lamina?

A

intermediate filaments

45
Q

this structure stabilizes nuclear structure

A

nuclear lamina

46
Q

this structure anchors chromatin

A

nuclear lamina

47
Q

this structure anchors nuclear pore complexes

A

nuclear lamina

48
Q

this structure regulates assembly and dissassembly of nuclear envelope during mitosis

A

nuclear lamina

49
Q

T/F a nucleus may contain multiple nucleoli

A

true

50
Q

what are Nups

A

nuecleoporins

8 Nups form an NPC nuclear pore complex

51
Q

how many proteins form an NPC nuclear pore complex

A

8 Nups nucleoporins

52
Q

3 classes of Nups

A
  • transmembrane Nups
  • structural Nups
  • FG Nups (phe and gly residues forming permeability barrier)
53
Q

what is the funciton of FG Nups

A

phe and gly residues form fishnet permeability barrier to larger molecules

54
Q

T/F hyrdophobicity is a big factor in transport through NPCs nuclear pore complexes

A

false - size and NLS (nuclear localization signal) are the biggest factors

55
Q

how does an NLS nuclear localization signal work

A
  • NLS binds importins (nuclear import receptors) in cytosol

- NLS importin complex repeatedly binds/unbinds FG Nups to travel across NPC

56
Q

how does an importin (nuclear import receptor) work

A
  • importin binds molecule with NLS
  • facilitates travel across FG Nups (binding/unbinding repeatedly)
  • once in nuclease, release cargo, exit to cytosol
57
Q

what 2 tests are performed to deterimine if prostate cancer has metastasized to another suspected location?

A

PET/CT scan

biopsy

58
Q

in α-β tubulin dimers, which points to the + end and which points to the - end of the microtubule filament?

A

β + end

α - end

59
Q

what are three tubulin monomers

A

α, β, γ

60
Q

what is the role of γ tubulin

A

assembles at - end to template correct assembly of microtubule

61
Q

what are the + and - ends of a cytoskeletal filament?

A 
\+ = fast growing end
- = slow growing end
62
Q

which are the most often targeted cytoskeletal elements for chemotherapy?

A

microtubules

63
Q

what are e microtubule motor proteins?

A

dynein

kinesin

64
Q

how many forms of α and β tubulin are there?

A

3 α types

5 β types

65
Q

what protein stabilizes microtubules on the - end?

A

MTOC

66
Q

what is a MAP protein

A

microtubule associated protein (e.g. tau)

stabilize microtubules

67
Q

this cytoskeletal element functions in shape, locomotion, contraction, cytokinesis, phagocytosis, and platelet aggregation

A

actin

68
Q

how many actin subunit types are there

A

3

α,β,γ

69
Q

how many actin subunit types form an actin filament?

A

only one type per filament

α, β, or γ

70
Q

T/F actin is the most commonly targeted cytoskeletal element for drugs

A

false - microtubules

actin drugs are too toxic for use in humans

71
Q

how do microtubules assemble

A

α and β tubulin dimerize and polimerize into protofilaments which then associate laterally

72
Q

how many protofilaments in a microtubule?

A

13

73
Q 
lamins
keratins
neurofilaments
vimentins
glial fibrillary acidic proteins GFAPS
desmin
are all examples of...
A

intermediate filament proteins

74
Q

how are intermediate filaments assembled?

A
  • α-helical monomers form protofilaments
  • α-helical protofilaments form coiled coil dimer
  • dimers associate in antiparallel tetramer
  • tetramers pack together in parallel
  • 8 tetramers twist into rope-like filament
75
Q

how many α-helical monomers in a mature intermediate filament?

A 
32?
protofilament
dimer
tetramer
8 tetramers = rope-like filament
76
Q

cytoskeletal elements:
strung beads
tubes
rope

A

strung beads - actin
tubes - microtubules
rope - intermediate filaments

77
Q

3 steps of cell movement

A
  • leading edge
  • adhesion/detachment
  • movement
78
Q

what is a lamellipodium

A

thin sheet-like projection that pulls cell through tissues

79
Q

filopodia

A

extension that explores ECM for growth (e.g. neurons and vessels)

80
Q

lamella

A

behind lamellipodia, couples actin to myosin II contractility

81
Q

what forms lamellipodia

A

polymerizing actin

82
Q

coflin

A

severs existing actin filaments

83
Q

this protein severs existing actin filaments

A

cofilin

84
Q

describe actin polymerization with the following proteins

  • fibronectin
  • integrin
  • Rac1
  • WASP/WAVE
  • Arp2/3
  • formin
  • cofilin
A
  • fibronectin (ECM) binds membrane integrins
  • integrins bind fibronectin, activate Rac1
  • Rac1 - activates WASP/WAVE
  • WASP/WAVE - activates Arp2/3
  • Arp2/3 - promotes actin branching/growth
  • formin - stabilizes actin
  • cofilin -severs existing actin filaments
85
Q

how do cells attach to ECM?

A

fibronectin (ECM protein) binds to integrin

transmembrane receptor protein

86
Q

what protein facilitates trailing edge detachment in cell movement?

A

Rho A

87
Q

what is the function of Rho A in cell movement?

A
  • inhibit Rac1 (inhibit actin polymerization)
  • stimulate actomyosin contractility
  • detach trailing edge
88
Q

what proteins facilitate lamellipodia extension?

A
  • integrins bind fibronectin, activate Rac1
  • Rac1 - activates WASP/WAVE
  • WASP/WAVE - activates Arp2/3
  • Arp2/3 - promotes actin branching/growth
  • formin - stabilizes actin
  • cofilin -severs existing actin filaments
89
Q

what proteins facilitate leading edge attachment?

A

fibronectin (ECM protein) binds to integrin

transmembrane receptor protein

90
Q

what proteins facilitate trailing edge detachment?

A
  • Rho A inhibit Rac1 (inhibit actin polymerization)
  • stimulate actomyosin contractility
  • detach trailing edge
91
Q

movement of the cell body is achieved through __ __

A

molecular clutching

92
Q

what is retrograde flow in terms of actin polymerization

A

actin polymerizes on + end, if not anchored, filament is pushed backward

93
Q

what kind of myosin is relevant in cell movement?

A

myosin II (non-muscle myosin NMII)

94
Q

how does molecular clutching work in cell movement

A

disengaged clutch = integrin not bound to actin
engaged clutch = integrin bound to fibronectin (ECM) and intracellular actin; actin polymerization causes forward force and movement

95
Q

what proteins are involved in the molecular clutch in cell movement

A
  • integrin, actin, fibronectin
  • disengaged clutch = integrin not bound to actin
  • engaged clutch = integrin bound to fibronectin (ECM) and intracellular actin; actin polymerization causes forward force and movement
96
Q

T/F Microtubules are repetitive filaments of covalently bound heterodimers

A

false - heterodimers are non-covalently bound

Biochem 1 (WPH) (15 decks)

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