Brainscape's Knowledge GenomeTM

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


See full index

metabolism > lipoproteins > Flashcards

lipoproteins Flashcards

1
Q

how are most fatty acids taken up from the body?

A

from the diet

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

why are TAGs packaged into lipoproteins?

A

not easily transported in the blood bc they’re hydrophobic

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

what do lipoproteins consist of?

A

cholesterol and apoproteins

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

what are chylomicrons?

A

dietary TAG lipoproteins

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

how is liver derived TAG released?

A

as VLDL

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

what are lipoproteins?

A

a method of transporting TAG, cholesterol and phospholipids and some vitamins between organs and tissues

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

describe the structure of lipoproteins

A

hydrophobic core with cholesterol esters and TAG

outer layer of phospholipids, free cholesterol and apoproteins

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

what do apoproteins do?

A

control fate of lipoproteins, interact with the cellular receptors and activate/inhibit enzymes

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

where are apoproteins found in a lipoprotein?

A

embedded (e.g. apoB) or loosely bound (e.g. apoC)

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

what is the main component and apoprotein of chylomicron?

A

TAG

B48

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

what is the main component and apoprotein of VLDL?

A

TAG

B100

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

what is the main component and apoprotein of IDL?

A

TAG, cholesterol

B100

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

what is the main component and apoprotein of LDL?

A

cholesterol

B100

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

what is the main component and apoprotein of of HDL?

A

protein

AI, AII, C, E

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

what does apoB100 do?

A

controls metabolism of LDL

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

what does apoB48 do?

A

controls chylomicrons

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

what does apoE do?

A

controls receptor binding of particles –> makes the chylomicron a target for disposal

18
Q

what does apoC do?

A

enzyme inhibitor

19
Q

where is lipoprotein lipase found?

A

epithelium adjacent to target cells

20
Q

which apoprotein activates LPL?

A

apoC2

21
Q

what does LPL do?

A

degrades TAG in chylomicrons and VLDL – releases free fatty acids and glycerol for uptake by adjacent cells

22
Q

where are chylomicrons formed?

A

in the lumen of the gut

23
Q

what are chylomicrons made up of?

A

TAG, esterified cholesterol, phospholipids, B48

24
Q

describe the life of a chylomicron?

A

formed in gut lumen
released by exocytosis into lacteals into the bloodstream
in the blood it exchanges components with high density lipoproteins
HDL donates ApoC-II and ApoE to chylomicron.
ApoC-II activates LPL, which breaks down TAG and unloads FAs.
Gives ApoC-II back to HDL and becomes a remnant. Bc of ApoE - taken up by liver

25
Q

what is cholesterol a precursor to?

A

steroids and bile acids

26
Q

what regulates the uptake of cholesterol into cells?

A

HMG-CoA

27
Q

what does transcription factor SREBP do?

A

regulates expression of HMG-CoA reductase –> regulates how much cholesterol is taken in

28
Q

where is HDL assembled?

A

liver and intestine

29
Q

where does HDL transport cholesterol?

A

from peripheral tissues to the liver for disposal via bile

30
Q

how does HDL scavenge free cholesterol and what does it do with it?

A

via the ABCA1 transporter and esterifies it to cholesterol esters

31
Q

what effect do LDL and HDL have on the risk of heart disease?

A

LDL - increases CVD risk

HDL - cardioprotective

32
Q

what conditions are caused by high TAG levels?

A

atherosclerosis –> risk of CHD and stroke

33
Q

what condition is common In diabetes?

A

dyslipidaemia

34
Q

what do oxidised LDLs promote?

A

formation of atherosclerotic plaques

35
Q

what causes oxidised LDL formation?

A

smoking and diabetes

36
Q

how does oxidised LDL lead to plaque formation?

A

Scavenger receptors aren’t feedback regulated by cholesterol –> macrophages become lipid laden –> foam cells –> fatty streaks in arterial wall –> plaque formation

37
Q

how do statins work?

A

blocking HMG-CoA reductase inside the cells –> can’t make cholesterol themselves so the cells have to meet cholesterol demand by taking cholesterol from the blood

38
Q

what is the mechanism of action of cholestryamine?

A

bind bile acids in the gut, preventing enterohepatic circulation

39
Q

what are the adverse effects of cholestryamine?

A

GI adverse effects mainly; nausea, flatulance, abdominal bloating, alteration of bowel habit

40
Q

what are the long term safety considerations of cholestryamine?

A

not systematically absorbed therefore the safety is good

fat soluble vitamins might be needed

metabolism (23 decks)

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