Lecture 14 - Lipoprotein Metabolism Flashcards Preview

Fuel Metabolism - 2016 > Lecture 14 - Lipoprotein Metabolism > Flashcards

Flashcards in Lecture 14 - Lipoprotein Metabolism Deck (29):
1

Which is the largest form of lipoprotein?

A. Chylomicron

B. VLDL

C. LDL

D. HDL

 

A

2

Which lipoprotein has the highest composition of protein?

A. Chylomicron

B. VLDL

C. LDL

D. HDL

D - HDL has slightly more protein content (52%) than lipid content

3

Which has the highest cholesterol and cholesterol ester content comprising its total lipid content?

A. Chylomicron

B. VLDL

C. LDL

D. HDL

C - LDL's lipid content is 48% cholesterol ester and 10% cholesterol

4

Which two types of lipo proteins have total lipid content that is comprised of more triglyercide than any other type of lipid?

A. Chylomicron/VLDL

B. VLDL/LDL

C. LDL/HDL

D. Only HDL

A - Chylomicron's lipid content is 88% triglyceride, while VLDL's lipid content is 56% lipid content.

5

Which type of lipoprotein does NOT contain the B apoprotein?

A. Chylomicron

B. VLDL

C. LDL

D. HDL

D - HDL contains only A, C, and E apoproteins.

6

Which is the smallest and densest lipoprotein?

A. Chylomicron

B. VLDL

C. LDL

D. HDL

D

7

Which lipoprotein contains B-48?

A. Chylomicron

B. VLDL

C. LDL

D. HDL

E. None of these

A

8

Which two apoproteins are ligands for cell surface receptors?

A. Apo A/Apo B

B. Apo A/Apo E

C. Apo B/Apo C

D. Apo B/Apo D

E. Apo B/Apo E

E

9

Which apoprotein acts as a ligand for LDL receptors?

A. Apo A

B. Apo B

C. Apo C

D. Apo E

B

10

Which apoprotein acts as a ligand for remnant receptors?

A. Apo A

B. Apo B

C. Apo C

D. Apo E

D

11

Which apoprotein activates lipoprotein lipase?

A. Apo A

B. Apo B

C. Apo C

D. Apo E

C

12

Which apoprotein is involved in enzyme activation for reverse cholesterol transport?

A. Apo A

B. Apo B

C. Apo C

D. Apo E

A

13

The function of lipoprotein lipase is to hydrolyze triglycerides in chylomicrons/VLDLs to release ______________ and generate remnant lipoproteins.

fatty acids

14

Where is lipoprotein lipase enriched?

A. Adipose tissue

B. Muscle tissue

C. Cardiac tissue

D. Sinusoidal surfaces of liver

E. All of the above except C

F. All of the above except D

F - lipoprotein lipase is enriched in adipose, muscle, and cardiac tissue.  

*Note: HEPATIC lipase is localized on sinusoidal surfaces of the liver versus capillaries everywhere.

15

Synthesis of lipoprotein lipase is stimulated by insulin in a specific cell type ONLY.  What is this specific cell type?

Adipocytes

16

Both hepatic lipase and lipoprotein lipase hydrolyze ______.

A. Triglycerides

B. Phospholipids

C. Cholesterol

D. Sphingolipids

A

17

Only hepatic lipase hydrolyzes:

A. Triglycerides

B. Phospholipids

C. Cholesterol

D. Sphingolipids

B

18

What are possibilities for the fate of IDLs that are not converted to LDLs by hepatic lipase?

A. Internalized by liver by binding to remnant receptors via Apo E

B. Internalized by liver by binding to remnant receptors via Apo B

C. Internalized by liver by binding to LDL receptors via Apo E

D. Internalized by liver by binding to LDL receptors via Apo B

E. Both A and D

F. Both B and C

 

E

19

What mediates the transfer of unesterified cholesterol and phospholipids from cell to HDL?

ABCA1

20

Cholesterol in HDL is esterified by:

A. ABCA1

B. LCAT

C. ACAT

D. CETP

E. Scavenger receptor B1

B

21

In the indirect pathway of reverse cholesterol transport, the transport of cholesterol esters from LDL to lipoprotein remnants is mediated by:

A. ABCA1

B. LCAT

C. ACAT

D. CETP

E. Scavenger receptor B1

 

D

22

In the direct pathway of reverse cholesterol transport, cholesterol esters are directly transferred to tissues from HDL via ____________.

A. ABCA1

B. LCAT

C. ACAT

D. CETP

E. Scavenger receptor B1

E

23

LDL receptors and remnant receptors are btoh involved in the uptake of _____ by the liver.

A. VLDL

B. IDL

C. HDL

D. Triglyerides

B

24

_________ are less localized and more prolific.

A. LDL receptors

B. Remnant receptors

 

A

25

Which of the following is true when comparing LDL and remnant receptors?

A. Remnant receptors bind Apo B-48, while LDL receptors bind Apo B-100

B. Remnant receptors bind Apo A-I, while LDL receptors bind Apo C-II

C. Remnant receptors bind Apo E, while LDL receptors bind Apo B-100

D. Remnant receptors and LDL receptors both bind Apo B-48

E. Remnant receptors and LDL receptors both bind Apo B-100

C

26

What are the two metabolic fates of IDLs?

 

1. Taken up by liver (via Apo E --> remnant receptors or via apo B --> LDL receptors)

2. Conversion to LDLs by hepatic lipase

 

27

A defect in the ABCA1 protein results in?

A. Familial hypercholesterolemia (FH)

B. Hypertriglyceridemia

C. Dybetalipoproteinemia

D. Abetalipoproteinemia

E. Tangier's diease

F. Fish Eye Disease

E

28

A defect in the enzyme that esterifies cholesterol in HDL causes which disease?

A. Familial hypercholesterolemia (FH)

B. Hypertriglyceridemia

C. Dybetalipoproteinemia

D. Abetalipoproteinemia

E. Tangier's diease

F. Fish Eye Disease

F - Fish Eye Disease is a defect in LCAT, which esterifies cholesterol in HDL.

29

Which is false regarding LDL receptors and scavenger receptors?

A. Both remove LDL from the plasma

B. Scavenger receptors have  alower affinity for LDL than LDL receptors

C. The synthesis of scavenger receptors is NOT regulated by cellular concentrations of choelsterol

D. The synthesis of LDL receptors is NOT regulated by cellular concentrations of cholesterol

E. Scavenger receptors are found on macrophages

D