2.4 Lipoproteins and Lipid transport Flashcards Preview

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Flashcards in 2.4 Lipoproteins and Lipid transport Deck (20):
0

What major tissue and organ destination does Chylomicron have?

Give up FFA to Adipose tissue, muscle and heart

1

Which molecule of lipid transport has the highest amount of TAGs as in weight?

Chylomicrons

2

Which lipid transport molecule has the highest % of cholesterols contained in it

LDL

3

Which molecule has the lowest density based on low protein/lipid ration

Chylomicrons --> VLDL --> IDL --> LDL

4

What is HDL's target tissue?

the Liver

5

What two apolipoproteins do chylomicrons receive as they move to deliver their FFA?

Apo C-II and Apo E from HDL

6

Name the 5 things that make up the composition of Chylomicrons?

TAGs
CHolesterol
Phospholipids
Apo B48
Apo A

7

About what percentage of TAGs in Chylomicrons are delivered to the peripheral tissues and liver?

80% to muscle, heart and adipose
20% to liver

8

Composition of Chylomicron Remnant

TAGs (90% removed so very little)
Cholesterol
Phospholipids
Apo B48
Apo A

9

Is there a difference between the TAGs in Chylomicrons and VLDL?

Chylomicrons contain dietary TAGs
VLDL contains TAGs synthesized from the liver from carbs

10

Composition of VLDL

Synthesized TAGs (from liver)
Cholesterol
Phospholipids
ApoB-100
ApoC-1
ApoC-3

11

Function of Apo C-II

To activate lipoprotein lipase and release FA from TAGs to adipose and muscle.

12

Does IDL contain Apo C-II and Apo E

Yes, it has not released them yet

13

Composition of LDL

Apo B-100
Cholesterol
Cholesterol Ester
Phospholipids

14

Function of Apo B-100

To be used as a ligand to recognize LDL receptors on the liver

15

What type of fats block LDL receptors on the liver and prevent LDL from being endocytosed?

Saturated fats

16

What happens when LDL returns to the liver and returns the cholesterol? What enzyme is affected?

There is an oversupply of cholesterol in the liver.
HMG CoA Reductase is down regulated and turns off cholesterol synthesis. This also down regulates LDL Receptor synthesis

17

What is the effect of Saturated fats blocking LDL receptors

Increased Cholesterol serum levels
Increases Cholesterol synthesis because HMG CoA Reductase is active with the small amount of cholesterol in the liver

18

Function of Apo E

Used on Chylomicrons to bind to liver receptors to become enocytosed

19

What plays a role as a reservoir for Apo C-II and Apo E

HDL