Cholesterol metabolism- Multiple choice questions

Q.1 – A gall stone that blocked the upper part of the bile duct would cause an increase in which of the following?

a) The excretion of fats in the feces

b) Formation of chylomicrons

c) Excretion of bile salts

d) Conjugation of bile acids

e) Recycling of bile salts

Q.2- An 8-year-old boy presents with orange-colored tonsils, a very low HDL levels, and an enlarged liver and spleen. He is diagnosed with Tangier disease. Tangier disease is a disease of cholesterol transport, such that cholesterol cannot properly exit the cell and form HDL. Which of the following statements best describes HDL?

a) It is produced in skeletal muscles

b) It scavenges cholesterol from cell membranes

c) Its major protein is apo E

d) It is formed when VLDL is acted upon by lipoprotein lipase

e) It activates ACAT

Q3- In contrast to secondary bile salts, which of the following is not a characteristic of primary bile salts

a) Are hydroxylated at position 17

b) Have an oxidized side chain

c) Can be conjugated to Taurine and glycine

d) Are reabsorbed in the intestine

e) Formed from cholyl co A .

Q.4-In the conversion of cholesterol to bile salts, which of the following statements best describes the process?

a) Carbon 8 is hydroxylated

b) The side chain can be conjugated with glycine or Taurine

c) The double bond is oxidized

d) The hydroxyl group ate 3 carbon remains in the beta position

e) It occurs in the bile duct.

Q.5- Which of the following statements best describes low-density lipoprotein  (LDL)?

a) It has the most Triacylglycerol and the least protein

b) It has more Triacyl glycerol than very-low-density lipoprotein(VLDL)

c) It has the lowest Triacylglycerol content

d) It has the highest protein content

e) It has the highest cholesterol content.

Q.6- Which of the following apoproteins is an activator of lipoprotein lipase ?

a) Apo A

b) Apo B

c) Apo C II

d) Apo D

e) Apo E

Q.7- Which of the following lipoproteins are the major carriers of Triacylglycerol ?

a) IDL and LDL

b) VLDL and LDL

c) Chylomicrons and VLDL

d) HDL and VLDL

e) Chylomicrons and HDL.

Q.8- A 60 -year-old woman presents with chest pain radiating to her left arm. She is diagnosed with Myocardial infarction and is prescribed statin medication. Statins inhibit HMG Co-A reductase. How does inhibition of HMG Co-A reductase cause the lowering of cholesterol and LDL levels?

a) It increase the serum level of HDL

b) It decreases serum level of LDL by promoting catabolism

c) It inhibits the formation of LDL from IDL

d) It inhibits the rate-limiting step in cholesterol biosynthesis

e) It inhibits synthesis of LDL receptors.

Q.9) -A 35-year-old woman presents with crushing substernal chest pain and shortness of breath. A coronary artery is occluded due to an atherosclerotic plaque, and she is diagnosed with having a myocardial infarction. Her serum cholesterol level is 700 mg/dl. The family history is positive for high cholesterol level and she seems to be having familial hypercholesterolemia. What is the possible biochemical defect in this genetic disorder?

a) High activity of HMG Co A reductase

b) Low activity of 7-α hydroxylase

c) Abnormal LDL receptors

d) More conversion of VLDL to LDL

e) Less concentration of HDL.

Q.10)- A 40- year-old man presents with severe pain in the legs upon walking. He is diagnosed with atherosclerotic plaques in the arteries of his legs. High levels of cholesterol and LDL contribute to the formation of atherosclerosis. Which of the following is digested to form LDL?

a) IDL

b) Chylomicrons

c) HDL

d) Cholesteryl esters

e)

Q.11- A 23-year-old female presents with low red blood cell count, corneal opacities and kidney insufficiency. She has been diagnosed with lecithin: cholesterol acyltransferase (LCAT) deficiency. In which of the following reactions LCAT is involved?

a) Transfer of cholesterol esters from HDL to VLDL

b) Hydrolysis of HDL

c) Uptake of cholesterol from liver cells

d) Converting cholesterol to Cholesteryl esters

e) Promoting uptake of HDL into liver cells

Q.12-  Which of the following is not a hypolipidemic drug?

a) Statin

b) Niacin

c) Folic acid

d) Clofibrate

e) Ezetimibe.

Q.13- The synthesis of HMG Co-A can take place-

a) only in mitochondria

b) Only in the cytoplasm of all mammalian cells

c) In the endoplasmic reticulum of all mammalian cells

d) In the lysosomes

e) In both cytosol and mitochondria.

Q.14- Which of the following best describes the role of cholesterol ester transfer protein (CETP)?

a) It converts cholesterol from LDL to cholesterol esters

b) It is the major protein of HDL

c) It exchanges cholesterol esters from HDL to other lipoproteins

d) It acts as a ligand for hepatic receptors of HDL

e) It is an activator of LCAT.

Q.15- Which of the followings  are  not  lipotropic agents?

a) Essential amino acids

b) Essential fatty acids

c) Vitamin A,C and E

d) Biotin and Pantothenic acid

e) Synthetic antioxidants

 

Key to Answers-

1)- a,     

2)-b,      

3)-a,      

4)-b,     

5)-e,      

6)-c,              

7)-c,      

8)-d,      

9)-c,      

10)-a,   

11)-d,              

12)-c

13)-b,   

14)-c,    

15)-d.