Brainscape's Knowledge GenomeTM

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


See full index

Metabolism > 4.2 Lipid transport > Flashcards

4.2 Lipid transport Flashcards

1
Q

5 groups lipids can be split into ?

A
  • triacylglycerol -> diacylglycerol & monoacylglycerol
  • fatty acids
  • cholesterol -> cholesterol esters
  • phospholipids
  • vitamins A, D, E and K
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Lipids are…

structurally …1.. group of compounds
…2.. molecules .3… in water

A
  1. diverse
  2. hydrophobic
  3. insoluble
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Lipids are transported in blood bound to ..1… :
* ~2% of lipids (mostly FA’s) are carried bound to .2…
* ~98% of lipids carried as ..3… consisting of ..4..

A
  1. carriers
  2. albumin
  3. lipoprotein particles
  4. phospholipids, cholesterols, cholesterol esters, proteins, triacylglycerols
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Plasma lipid concentration of triacylglycerol

A

1.0 mmol/L

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

Plasma lipid concentration of phospholipids

A

2.5 mmol/L

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

Plasma lipid concentration of total cholesterol

A

5.0 mmol/L

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

Plasma lipid concentration of cholesterol esters

A

3.5 mmol/L

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

Plasma lipid concentration of free FA’s

A

0.4 mmol/L

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

Lipoprotein structure:
* …1… surface coat (shell)
* …2… lipid core

A
  1. polar
  2. non-polar
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Phospholipids are classified according to their ….1… e.g. ?
choline -> ..2…
inositol -> ..3..

A
  1. polar head group
  2. phosphatidylcholine
  3. phosphatidylinositol
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

How is some and most cholesterol obtained ?

A
  • some = from diet
  • most = synthesised in liver
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

what is cholesterol to cell membranes ?

A

an essential structural component that modulates fluidity

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

Cholesterol is a precursor for what 3 substances ?

A
  • steroid hormones
  • bile acids
  • vitamin D
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

List examples of steroid hormones that cholesterol is a precursor for …

A

TACO
Testosterone
Aldosterone
Cortisol
Oestrogen

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

How is cholesterol transported around the body ?

A

as cholesterol ester, in some lipoproteins

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

what are apolipoproteins ?

A

apoproteins associated with lipoprotein particles

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

Apolipoproteins can be ..1… or ..2…

what’s difference between the 2 , Include 2 examples of apolipoproteins for each?

A
  1. peripheral = loosely bound to surface [apoC and apoE]
  2. integral = passing through phospholipid bilayer [apoA, apoB]
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

structural role of apolipoprotein ?

A

packaging water insoluble lipid into soluble form

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

functional role of apolipoprotein

A

co-factor for enzymes and ligands for cell surface receptors

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

6 major classes of apolipoproteins ?

A

A-E and H

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

In which lipoprotein particles is apolipoprotein B (apoB) found?

A
  • chylomicrons
  • VLDL
  • IDL
  • LDL
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

In which lipoprotein particles is apoAI found?

A

HDL

23
Q

In which lipoprotein particles is apoC and apoE found?

A
  • chylomicrons
  • VLDL
  • HDL
24
Q

what are the 5 distinct classes of plasma lipoprotein particles ?

A
  • chylomicrons
  • VLDL (very low density lipoproteins)
  • IDL (intermediate density lipoproteins)
  • LDL (low density lipoproteins)
  • HDL (high density lipoproteins)
25
Q

Each plasma lipoprotein particles contains variable content of what ?

A

apolipoprotein
triacylglycerol
cholesterol
cholesterol ester

26
Q

Plasma lipoprotein particles that are :
1. main carriers of TGs
2. main carriers of cholesterol esters

A
  1. Chylomicron, VLDL
  2. IDL, LDL, HDL
27
Q
  1. where are chylomicrons formed ?
  2. transported to bloodstream via what ?
A
  1. Intestinal mucosa (small intestine)
  2. lymphatic vessels
28
Q

Lipoprotein density is measured how ?

A

ultracentrifugation

29
Q

Lipoproteins relationship between particle diameter and density

A

they are inversely proportional

30
Q

Chylomicrons mainly carry ..1.. to ..2… tissue especially ..3.. tissue

A
  1. dietary triacylglycerols
  2. peripheral
  3. adipose
31
Q

chylomicrons are normally only present in blood ..1… hr after a meal and then cleared, IF persistence after ..2.. hr it’s a ..3…

A
  1. 4 - 6
  2. 6
  3. clinical problem
32
Q

6 components looked for in a cholesterol blood test ?

A
  • total cholesterol (TC)
  • non-HDL-cholesterol
  • LDL-cholesterol (LDL-C) ‘bad’
  • HDL-cholesterol (HDL-C) ‘good’
  • Total cholesterol: HDL-C ratio
  • triglyceride (TG)
33
Q

what is non HDL-cholesterol ?

A

total cholesterol minus HDL-cholesterol

34
Q

Ideal value of total cholesterol ?

A

5 mmol /L or less

35
Q

Ideal value of non HDL-cholesterol ?

A

4 mmol/L or less

36
Q

Ideal value of LDL-cholesterol?

A

3 mmol/L or less

37
Q

Ideal value of HDL-cholesterol?

A
  • over 1 mmol/L (men)
  • over 1.2 mmol/L (women)
38
Q

Ideal value of total cholesterol: HDL-C ratio ?

A

ratio above 6 considered high risk - so lower the ratio the better

39
Q

Ideal value of triglyceride in fasted sample ?

A

< 2 mmol/L

40
Q

Hyperlipoproteinaemia:
1. raised ….
2. caused by: ….
3. defects in ….

A
  1. plasma levels of one or more lipoprotein classes
  2. over-production/ under-removal
  3. enzymes, receptors, apoproteins
41
Q

6 main classes of hyperlipoproteinaemia ?

A

I , IIa, IIb, III, IV, V

42
Q

type I hyperlipoproteinaemia

  1. in fasting plasma …. present ?
  2. no link with ….
  3. Cause ?
A
  • chylomicrons
  • coronary artery disease
  • defective lipoprotein lipase
43
Q

type IIa hyperlipoproteinaemia

  1. raised … ?
  2. associated with ….
  3. Caused by ?
A
  1. LDL
  2. coronary artery disease that may be severe
  3. defective LDL receptor
44
Q

type IIb hyperlipoproteinaemia

  1. raised … ?
  2. associated with ….
  3. Caused by ?
A
  1. LDL and VLDL
  2. coronary artery disease
  3. unknown defect
45
Q

type III hyperlipoproteinaemia

  1. raised … ?
  2. associated with ….
  3. Caused by ?
A
  1. IDL and chylomicron remnants
  2. coronary artery disease
  3. defective apoprotein (apoE)
46
Q

type IV hyperlipoproteinaemia

  1. raised … ?
  2. associated with ….
  3. Caused by ?
A
  1. VLDL
  2. coronary artery disease
  3. unknown defect
47
Q

type V hyperlipoproteinaemia

  1. raised … in fasting plasma ?
  2. associated with ….
  3. Caused by ?
A
  1. chylomicrons and VLDL
  2. coronary artery disease
  3. unknown cause
48
Q

3 clinical signs of hypercholesterolaemia,

resulting from cholesterol depositions in various areas of body ?

A
  • Xanthelasma = yellow patches on eyelids
  • Tendon Xanthoma = nodules on tendon
  • Corneal arcus = white cicrle around eye, common in older people (different to brushfield spots in down syndrome!)
49
Q

first approach treatment of hyperlipoproteinaemia ?

A

DIET
* reduce cholesterol and saturated lipids in diet
* increase fibre intake

LIFESTYLE
* increase exercise
* stop smoking

50
Q

If no response to first approach treatment of hyperlipoproteinaemia (diet & lifestyle) -> drugs are used which are what ?

A
  • statins
  • bile salt/ acid sequestrants
51
Q

Statins used to treat hyperlipoproteinaemia reduce and increase what ?

A
  • reduce cholesterol synthesis = inhibiting HMG-CoA reductase
  • increase LDL receptor / HSL expression
52
Q

2 examples of statins that inhibit HMG-CoA reductase and reduce cholesterol synthesis

A
  • atorvastatin
  • simvastatin
53
Q

Examples of bile salt/acid sequestrants as treatment of hyperlipoproteinaemia

A
  • bind bile SALTS in GI tract = cholestyramine (questran)
  • bind bile ACIDS in GI tract = colestipol (colestid)

Metabolism (21 decks)

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