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Flashcards in ZIMA Exam Questions Deck (34)
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1
Q

A particle composed of proteins and RNA that binds to signal sequences and targets polypeptiude chains to the ER:

A

SRP (is the ER)

2
Q

What transmembrane protein mediates fusion of vesicles and target membranes

A

FUSION of vesicles: SNARE

3
Q

The membrane channel through which polypeptide chains are transported into the ER is?

A

Translocon

4
Q

A vesicular compartment involved in vesicle formation

A

Clathirin or Coat proteins

5
Q

What phospholipid is the most important in cell signaling?

A

Phosphatidlyinositol (PI)

also important in vesicular formation

6
Q

What is the function of a SNARE protein?

A

it mediates FUSION of vesicles and target membranes

7
Q

What happens if you inhibit the sodium potassium pump?

A

Glucose transport decreases

pH goes down (increased H in cell)

calcium accumulates inside the cell

8
Q

What is the major lipid in the bilayer?

A

Phospholipids

9
Q

Spingomyelin vs phosphoglycerides

A

Glyceride has glycerol

10
Q

Major factor driving lipid bilayer formation

A

Hydrophobic vs hydrophillic parts

11
Q

Major factor in STABILITY of plasma membrane

A

Van der waals forces/ intermolecular interactions between fatty acid chains

12
Q

Explain how Tc relates to fully saturated vs non saturated lipids

A

Fully saturated lipid will have higher Tc (easier to freeze)

Lipid with nonsaturated chains have lower Tc (harder to freeze)

13
Q

What two things make up a raft?

A

Spingomyelin and cholesterol

14
Q

What is the major component that establishes the RMP

A

K leak chanels (90% contribution)

15
Q

What type of pump is the Na/K ATPase

A

Na/K ATPase is a P type pump

16
Q

What happens during the repolarization of an AP

A

Repolarization: delayed activating K+ channels open

Sodium channels become inactivated

17
Q

What is “gating”

A

Shift between open and closed states

18
Q

What is the fastest way lipids move in the bilayer?

Slowest way lipids move in the bilayer?

A

Fastest: lateral diffusion

Slowest: flip flop

Remember, the translocase catalyzes the flip flop mechanism

19
Q

If you have posion in your leg, where you get an Action Potential but your leg itself does not contract…. what happened?

A

The toxin is blocking your NICOTONIC receptor

20
Q

What does BOTOX do

A

Messes with snare mechanism, preventing vesicle fusion

21
Q

What happens to the action potential if sodium channels and potassium channels open at the same time?

A

There won’t be an AP

22
Q

What structure is involved in apoptosis?

A

Phosphatidyl-serine is involved in apoptosis

Remember, normally PS faces inward, but in apoptosis, the scramblase makes it flip and face outwards, signaling apoptosis

23
Q

What happens to the AP if you block K channels?

A

If you block K channel, the AP will SLOWLY repolarize

24
Q

Post-translational transport vs co-translational transport

A

Nucleus: post-translational, fully folded

Mitochondria: post-translational, fully folded

ER: co-translational

25
Q

What is the energy source for transport of proteins into the nucleus?

A

Nucleus: GTP

26
Q

What is the energy source of protein transport into the mitochondria?

A

ATP (and the membrane potential)

27
Q

What is the functional role of protein glycosylation?

A

Protein glycosylation in the ER: Proper protein folding

28
Q

What is the function of the coat proteins and clathirin

A

Coat proteins and clathirin: innvolved in vesicular formation

29
Q

What do ABC transporters do?

A

They extrude small molecules from the cell

30
Q

What is the contribution of Na/K ATPase to the RMP?

A

Tiny contribution, only helps like 10%

31
Q

TOM vs TIM

A

Outer membrane vs inner membrane of mitochondria

32
Q

What is special about protein transport into the ER?

A

Translation is stopped, remember co-translational

SRP stops translation

33
Q

PIPs can or cannot form vesicles alone?

If you don’t have an adaptor protein what is the concenquence?

A

PIPs cannot form vesicles alone

No adaptor protein… no vesicular formation

34
Q

What is the major ion that works with SNARE

A

Calcium