Fatty Acid Metabolism- Multiple Choice Questions (Solved)-set-4

Q.1- Glucose can be converted to Glycerol-3-P through which of the following intermediates?

a) Glycerol

b) Dihydroxyacetone phosphate

c) Acetyl co A

d) Pyruvate

e) Malate.

Q.2- Which of the following supplies the 2 carbon units that are added to the elongation of the fatty acid chain?

a) Acetyl co A

b) Malonyl co A

c) β- Keto acyl co A

d) Glucose

e) Pyruvate.

Q.3-The conversion of Acetyl co A to Malonyl CoA requires which of the following?

a) Biotin

b) Adenosine Diphosphate (ADP)

c) NADPH

d) H2O

e)  Folic acid.

Q.4- NADPH is synthesized by the action of which of the following enzymes?

a) Glucose-6-P dehydrogenase

b) Pyruvate dehydrogenase

c) Acetyl co A carboxylase

d) Lipoprotein lipase

e) Glycerol kinase.

Q.5- A 45-year-old female presents with severe upper abdominal pain, nausea, and vomiting. She is diagnosed with pancreatitis (inflammation of the pancreas). Her serum triglyceride level is found to be 3000 mg/dl and is deemed as the cause for Pancreatitis. To form Triacylglycerol, which of the following is added to diacylglycerol?

a) Glycerol

b) Glycerol-3-Phosphate

c) Fatty acyl co A

d) Acetyl co A

e) Succinyl co A.

Q.6- A 35-year-old man presents with yellow xanthomas on his skin and hepatomegaly (enlarged liver). His Triglyceride level is 1500 mg/dl. He is diagnosed with type V hyperlipidemia. Triglycerides are primarily synthesized in which of the following tissues?

a) Skeletal muscle

b) Heart muscle

c) Liver

d) Spleen

e) Blood cells.

Q.7- An 18-year-old female is diagnosed as obese. She maintains a sedentary life style and eats a high-fat, high-sugar diet. Maintenance of this diet and lifestyle has led to lipogenesis and obesity. Which of the following affects excessive fatty acid synthesis?

a) Glycerol is obtained through glycolysis

b) Fatty acids are excessively synthesized from Acetyl co A

c) NADPH is excessively obtained from HMP pathway

d) Triglycerides are excessively synthesized

e) All of the above.

Q.8- A 30- year-old pregnant woman has a sugar craving and consumes a hot fudge sundae. Her serum glucose level increases, which causes the release of Insulin. Insulin is known to increase the activity of acetyl co A carboxylase, the rate-limiting enzyme of fatty acid biosynthesis. Which of the following best describes this regulatory enzyme?

a) It is activated by carboxylation

b) It catalyzes a reaction that condenses an acetyl group with malonyl group

c) It catalyzes a reaction that requires biotin and ATP

d) It converts Malonyl co A to Acetyl co A

e) It is activated by malonyl co A.

Q.9- A 16-year-old female presents with xanthomas on her eyelids. She is found to have a rare genetic deficiency of lipoprotein lipase and is diagnosed with type 1 hyperlipidemia. In this disorder, chylomicrons are abnormally elevated in the serum. In what type of cell are triacylglycerols packaged into chylomicrons?

a) Intestinal epithelial cells

b) Liver cell

c) Muscle cell

d) Heart cell

e) Adipose cell.

Q.10- A 50-year-old, alcoholic male presents with a swollen face, distended abdomen, and an enlarged fatty liver. Fatty acids react with glycerol-3-P to form triglycerides, which accumulate to cause fatty liver. The liver has glycerol kinase, while adipose tissue lacks glycerol kinase. As a result, in adipose tissue, which of the following occurs?

a) Glucose can not be converted to DHAP

b) Glycerol can not be converted to Glycerol-3-P

c) DHAP can not be converted to Glycerol-3-P

d) Diacylglycerol can not be converted to Triacylglycerol

e) Triacylglycerols can not be stored.

Q.11- A 25-year-old man is brought to the emergency room after a motor vehicle accident. He has a dislocated hip, rib fractures, and a facial laceration. The toxicology screen shows a high level of ethanol in his blood. Oxidation of ethanol produces acetaldehyde and NADH. A high level of NADH relative to NAD + slows TCA cycle and promotes the conversion of which of the following reactions?

a) Dihydroxyacetone phosphate to glycerol-3-P

b) Glycerol-3-P to Dihydroxyacetone phosphate

c) Citrate to isocitrate

d) Malate to Oxaloacetate

e) All of the above.

Q.12- A 35-year-old woman presents with flatulence, bloating, and steatorrhea (fat in the stool). She had been eating large amounts of potato chips that were made using Olestra, a fat substitute. Normally, dietary triacylglycerol is hydrolyzed into components that are reconstructed into triacylglycerols that become a component of chylomicrons. In the intestinal cell, the initial precursor for fatty acid synthesis is which of the following?

a) Glycerol

b) Glycerol-3-P

c) 2-Mono acyl glycerol

d) Phosphatidic acid

e) Acetyl co A.

Q.13- The complete oxidation of odd chain fatty acid produces which of the following?

a) Acetyl co A only

b) Acetyl co A and Propionyl co A

c) Butyryl co A

d) Palmitoyl co A

e) Propionyl co A only

Q.14- The activation of long-chain fatty acids requires which of the following components?

a) 2 ATP

b) 2 ATP and Co A

c) 2 ATP, Co A, and fatty acyl co A

d) Fatty acylcarnitine

e) Carnitine acyltransferase I and II.

Q.15- Which of the following statements best describes the β- oxidation of fatty acids?

a) One Acetyl co A is produced in each turn of the β- oxidation spiral

b) β- oxidation of fatty acids is an extramitochondrial process

c) The enzymes present in the form of multienzyme complexes

d) The intermediates are carried by Acyl carrier protein

e) 129 ATPs are required for the formation of one mole of Palmitic acid.

Q.16- β- oxidation of long-chain fatty acids occurs primarily in which of the following locations?

a) Cytosol

b) Peroxisomes

c) Mitochondria

d) Endoplasmic reticulum

e) Golgi apparatus.

Q.17- How many carbons are removed from fatty acyl co A in one turn of the β- oxidation spiral?

a) 1

b) 2

c) 3

d) 4

e) 6

Q.18- β- oxidation of fatty acids is promoted by which of the following?

a) ATP

b) NAD +

c) FADH2

d) Acetyl co A

e) Propionyl co A.

Q.19- What is the role of Thiolase in the β- oxidation of fatty acids?

a) Cleaves of Co A

b) Cleaves the bond between α- and β- carbons

c) Adds H2O across the double bond

d) Generates NADH

e) Generates FADH2

Q.20- Which of the following products is released in α-oxidation of fatty acids?

a) Co A

b) CO2

c) H2O

d) Acetyl co A

e) Hydrogen peroxide.

Q.21- A 16-year-old extremely slender girl presents with a bodyweight that is 35% below expected. She still feels herself to be obese and severely restricts her food intake. She is diagnosed with Anorexia Nervosa. In this patient, due to improper dietary intake, the breakdown of fatty acids is required to provide energy. Which of the following substance is formed in the first step of the beta-oxidation of fatty acids?

a) ATP

b) Co A

c) Fatty acyl co A

d) Carnitine

e) Malonyl co A.

Q.22- A 5-year-old boy presents with altered mental status, heart failure, and muscle weakness. His serum level of ketones and glucose is abnormally low. He is diagnosed with primary carnitine deficiency. In which of the following is carnitine directly involved?

a) Activation of fatty acids

b) Transport of fatty acyl co A

c) β-Oxidation

d) ω- Oxidation

e) α- Oxidation.

Q.23- A 10-year-old girl presents with difficult walking, muscle weakness, and altered mental status. She is diagnosed with carnitine acyltransferase deficiency. Carnitine acyl Transferase-I catalyzes a reaction that produces which of the following?

a) Fatty acyl co A

b) Fatty acyl Carnitine

c) Fatty enoyl co A

d) β- OH- Acyl co A

e) β- Keto acyl co A.

Q.24- An obese, 40-year-old woman, who recently underwent gastric bypass surgery, presents with severe vomiting due to rapid intake of large quantities of food, which must be avoided after gastric bypass surgery. She had successfully lost 10 Ib over the last month after the surgery due to the mobilization of fat stores to provide acetyl co A and energy. When palmitoyl co A is oxidized, how many Acetyl co A are produced?

a)1

b) 10

c) 6

d) 8

e) 4

Q.25- A 16-year-old marathon runner trains by running 15 miles every morning, requiring a constant supply of ATP. Approximately How many ATP are produced when palmitoyl co A is oxidized to CO2 and H2O?

a) 100

b) 129

c) 136

d) 96

e) None of the above.

 

Key to answers-

1)-b,    

2)-b,    

3)-a,      

4)-a,    

5) –c,    

6)-c,    

7)-e,     

8)-c,      

9)-a,      

10)-b,   

11)- a,      

12)- c,    

13)- b,   

14)- b,  

15)- a,  

16)- c,   

17)- b,  

18)- b,  

19)- b,  

20)- b,  

21)-c,    

22)- b    

23)- b,  

24)-d,    

25)-b.