Brainscape's Knowledge GenomeTM

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


See full index

DIT > 1E Foundations 5 - Cell Biology - Plasma membrane > Flashcards

1E Foundations 5 - Cell Biology - Plasma membrane Flashcards

1
Q

Name the different types of phospholipids in the plasma membrane?

A
  • Phosphatidylcholine (aka lecithin)
  • Phosphatidylserine
  • Phosphatidylinositol
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Components of the plasma membrane?

A
  • Phospholipid bilayer
  • Proteins (more protein than phospholipids)
  • Glycoprotein
  • Glycolipids
  • Sphingolipids
  • Cholesterol (15% of plasma membrane)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Tyrosine kinase receptors function?

A

Transfer a phosphate group (phosphorylate) from ATP to selected tyrosine side chains on specific protein including itself (autophosphorylation).
The first step after binding of ligand is to autophosphorylate.

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

What type of pass receptor is PDGFR and other growth factor receptors?

A

single-pass transmembrane

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

Type of receptor? (Insulin and IGF-I)

A

Four subunits:

  • 2alpha (bound by disulfide bonds) bind extracellular ligand
  • 2beta (tyrosine kinase activity)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Definition of a Kinase

A

Uses ATP to add phosphate groups

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

Definition of a Phosphatase

A

Removes phosphate groups

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

Definition of a Phosphorylase

A

Adds inorganic phosphate without using ATP

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

Definition of a Dehydrogenase

A

Oxidizes substrates by using an electron acceptor (NAD or NADP)

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

Definition of a Carboxylase

A

Adds carbon units with help of biotin

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

Where is the majority of Na+

A

Extracellulary

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

Where is the majority of K+

A

Intracellulary

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

What is the ratio of Na+/K+ exchanged by the Sodium-Potassium ATPase?

A
  • 3Na+ out

- 2K+ in

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

What drugs can inhibit the sodium-potassium ATPase?

A
  • Cardiac glycosides (Digoxin, Digitoxin)

- Ouabain (inhibits by binding to K+ site)

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

What is the end-result of blocking the sodium-potassium ATPase?

A

Indirect inhibition of Na+/Ca2+ exchange –> Increased intracellular Ca2+–> increased cardiac contractility

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

What does Clathrin bind to?

A

Adaptin

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

What is the function of Dynamin?

A

It pinches of the developing clathrin-coated vesicle so that it becomes a vesicle

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

What does Adaptin bind to on the other side of clathrin?

A

A cargo receptor

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

In receptor-mediated endocytosis what happens after uncoating of clathrin from endosomal vesicle?

A

The receptor is recycled back to the plasma membrane and the vesicle fuses with a lysosome

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

What can be an outcome of an LDL receptor with an abnormal coated pit binding site?

A

Familial hypercholesterolemia

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

What is the function of Arachidonic Acid derivatives?

A

Tissue-tissue communication. They are communicating substances

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

Name three major derivatives of Arachidonic acid

A
  • Leukotrienes
  • Prostacyclines
  • Prostaglandins
23
Q

Arachidonic acid derivative pathway. Step 1?

A

Membrane phospholipid (specifically Phosphatidylinositol) is converted to Arachidonic Acid by Phospholipase A2.

24
Q

What can inhibit Phospholipase A2?

A

Corticosteroids

25
Q

Arachidonic acid derivative pathway. Step 2A1?

A

Arachidonic acid is converted to Hydroperoxides by Lipoxygenase

26
Q

What can inhibit Lipoxygenase?

A

Zileuton

27
Q

Zileuton is used as asthma medication because it blocks the production of?

A

Leukotrienes

28
Q

Arachidonic acid derivative pathway. Step 2A2?

A

Hydroperoxides are converted to Leukotrienes (LTB4, LTC4, LTD4)

29
Q

What is associated with LTB4?

A

Neutrophil chemotaxis (Increased LTB4 attracts Neutrophils)

30
Q

What is associated with LTC4 and LTD4?

A

Increased bronchial tone (which is why blocking of Leukotrienes is helpful in asthma patients)

31
Q

What drugs block the Leukotriene receptors? (specifically LTC4 and LTD4)

A
  • Zafirlukast

- Montelukast (Approved for pediatric population)

32
Q

Arachidonic acid derivative pathway. 2B1?

A

Arachidonic acid is converted to Endoperoxides (PGG2, PGH2) by Cyclooxygenase (COX-1, COX-2)

33
Q

Only COX-2 inhibitors?

A

Celecoxib

34
Q

Irreversible inhibitor of COX

A

Aspirin

35
Q

Why does acetaminophen not have antiplatelet and antiinflammatory effects?

A

Acetaminophen is inactivated peripheraly

36
Q

Inhibitors of COX

A

NSAIDS, celecoxib, Aspirin, Acetaminophen

37
Q

Arachidonic acid derivative pathway. Step 2BA?

A

Endoperoxides are converted to Prostacyclin (PGI2) (“Platelet Gathering Inhibitor”)

38
Q

Effects of PGI2?

A

Decreased:

  • Platelet aggregation
  • Vascular tone
  • Bronchial tone
  • Uterine tone
39
Q

Analogs of Prostacyclins can be used to treat?

A

Raynaud phenomenon and pulmonary hypertension (due to vasodilatory effects)

40
Q

Arachidonic acid derivative pathway. Step 2BB?

A

Endoperoxides are converted to Prostaglandins (PGE2, PGF2a).

41
Q

Effects of Prostaglandins?

A
  • Increased Uterine tone (Induce labour, Abortifacient (induce uterine contractions))
  • Decreased: Vascular tone and Bronchial tone
  • Increased gastric mucous production
42
Q

Arachidonic acid derivative pathway. Step 2BC?

A

Endoperoxides are converted to Thromboxane

43
Q

How is Thromboxane associated with thrombose formation?

A

Thromboxane is prothrombotic

44
Q

Effects of Thromboxane?

A

Increased:

  • Platelet aggregation
  • Vascular tone
  • Bronchial tone
45
Q

Which Arachidonic acid derivative causes Increased bronchial tone?

A
  • Leukotrienes (LTC4, LTD4)

- Thromboxane (TXA2)

46
Q

Which Arachidonic acid derivative causes decreased bronchial tone?

A
  • Prostacyclin (PGI2)

- Prostaglandins (PGE2, PGF2a)

47
Q

Which Arachidonic acid derivative causes increased platelet aggregation

A

Thromboxane (TXA2)

48
Q

Which Arachidonic acid derivative causes decreased platelet aggregation?

A

Prostacyclin (PGI2)

49
Q

Which Arachidonic acid derivative causes increased uterine tone?

A

Prostaglandins (PGE2, PGF2a)

50
Q

Which Arachidonic acid derivative causes decreased uterine tone?

A

Prostacyclin (PGI2)

51
Q

Which Arachidonic acid derivative causes increased vascular tone?

A

Thromboxane (TXA2)

52
Q

Which Arachidonic acid derivative causes decreased vascular tone?

A
  • Prostacyclin (PGI2)

- Prostaglandins (PGE2, PGF2a)

53
Q

What are the two most abundant substances in plasma membranes?

A

Proteins and Phospholipids

54
Q

What drugs act on the arachidonic acid product pathway? What enzymes do they affect?

A 
Corticosteroids:
-Inhibit phospholipase A2
Zileuton:
-Inhibits lipoxygenase
Zafirlukast and Montelukast
-Inhibit leukotriene receptors
NSAIDs, acetaminophen, COX-2 inhibitors, aspirin
-Inhibit cyclooxygenase

DIT (11 decks)

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