Question

About utilization of fatty acids to generate ATP, which of the following is INCORRECT?

a). It is first activated by ATP to form fatty acyl-CoA in the cytosol
b). Fatty acyl-CoA needs carnitine acyltransferases to translocate to mitochondria c). Each round of beta-oxidation releases 1 acetyl CoA, 1 NADH and 1 NADPH
d). The translocation process is repressed by high levels of insulin
e). it is repressed by active fatty acid biosynthesis

16. Biosynthesis of fatty acids in mammalian hepatocytes needs NADPH. In addition to pentose pathway, which of the following biochemical processes can provide additional NADPH for biosynthesis?

a) An alternative glycolytic pathway, ED pathway, generates NADPH b) Malic enzyme-catalyzed dehydrogenation of malate
c) Dehydrogenation of pyruvate in cytosol
d) β-oxidation of fatty acids in the cytosol recovers NADPH

e) Dehydrogenate citrate in cytosol

17. Assume a type of lipase identified in adipose tissues which can be activated by an unknown hormone. Upon activation, it releases fatty acids into circulation as fuel supply. Functionally, this hormone is unlikely to be:

a). glucagon b). insulin
c). epinephrine d). T3
e). T4

18. Pancreas is important for metabolism because it produces the following, EXCEPT for:

a). insulin
b). glucagon c). lipases
d). thyroids e). proteases

19. Which of the following pathway in skeletal muscle will not be stimulated by AMPK?

a). glycogenolysis

b). glycolysis
c). gluconeogenesis

d). beta-oxidation

e). krebs cycle

30. Which one is a cofactor needed for the glycogenolysis?

For questions 37-40, refer choices given below:

a). Glut1 b). Glut2 c). Glut3 d). Glut4 e). SGLT

37. The one whose cell surface localization is enhanced by insulin signaling pathway is?
38. Which one is expressed abundantly on neuronal cells?
39. Which one has a large Km and expressed mainly in hepatocytes and pancreatic alpha/beta-cells? 40. Which one is abundantly expressed in red blood cells to ensure supply of glucose to erythrocytes?

Answer 1

About utilization of fatty acids to generate ATP, which of the following is INCORRECT?

c). Each round of β-oxidation releases 1 acetyl CoA, 1 NADH and 1 NADPH.

β-oxidation doesn’t produce NADPH. Each round of β-oxidation produces 1 acetyl-CoA, 1 NADH, and 1 FADH2.

Other options are correct regarding β-oxidation.

a). Fatty acid is first activated by ATP to form fatty acyl-CoA in the cytosol.

Fatty acids are activated to fatty acyl-CoA by acyl-CoA synthetases with the help of ATP.
b). Fatty acyl-CoA needs carnitine acyltransferases to translocate to mitochondria.

Carnitine acyltransferases on the outer and inner mitochondrial membrane help translocating acyl-CoA in the form of acyl-carnitine form the cytosol to the mitochondrial matrix.

d). The translocation process is repressed by high levels of insulin

Insulin represses lipolysis to minimize blood glucose levels.

e). it is repressed by active fatty acid biosynthesis.

Fatty acid biosynthesis repressed β-oxidation of fatty acids. It is feedback regulation.