Question

1. In fatty acid oxidation, ATP is consumed in which step?

a. Transport of acyl CoA into the mitochondria

b. Formation of the acyl-CoA

c. Thiolysis of the ketoacyl- CoA intermediate

d. Conversion of acyl-CoA into enoyl-CoA

e. Formation of malonyl-CoA

2. If b-oxidation and citric acid cycle reactions completed the oxidation 3 molecules of hexanoic acid (6 carbon carboxylic acid) to CO₂, how many CO₂, NADH and FADH₂ would be produced? (SHOW WORK)

CO₂               _______

NADH           _______

FADH₂         _______

3. Match each process with the location within the body/cell where it occurs: Chose all that apply.

   b-oxidation of fatty acids ________                                   a. Intestinal lumen

   emulsification of TAG _______ b. intestinal brush border cells

   fatty acid synthesis ________ c. mitochondrial matrix

   formation of chylomicrons ________                                 d. cytosol

   formation of micelles _________ e. peroxisomes

   formation of fatty acyl-CoA ________

4. A defective Translocase component of the Fatty acid transport system, or a deficiency of carnitine would likely result in:

a. Higher than normal levels of Fatty Acyl CoA in the mitochondrial matrix

b. Higher than normal levels of Fatty Acyl CoA in the cytosol

c. Higher than normal levels of acetyl CoA in the cytosol

d. Higher than normal levels of acetyl CoA in the mitochondrial matrix

e. Higher than normal levels of acyl Carnitine in the mitochondrial matrix

Answer 1

1. b Formation of Acyl-Co A

free fatty acids from cytosol cannot enter the mitochondrial membranes directly. Hence, fatty acids are activated into Fatty Acyl-CoA with ATP consumption and are transported into mitochondrial matrix via Carnitine Shuttle system

fatty acid + Co A + ATP<----------------> Fatty Acyl-CoA + AMP+ PPi

2. Hexanoic Acid undergoes 2 cycles of Beta-Oxidation and converts into 3 molecules of Acetyl Co A.

FADH₂ produced during  Beta-Oxidation of 3 molecules of  Hexanoic Acid =3 x 2 =6

NADH  produced during  Beta-Oxidation of 3 molecules of  Hexanoic Acid= 3 x 2= 6

NADH  produced during TCA cycle of 3 molecules of  Hexanoic Acid= 3 x 3 (Acetyl CoA) x 3 (NADH) = 27

NADH  produced during  Beta-Oxidation of 3 molecules of  Hexanoic Acid= 3 x 3 (Acetyl CoA) x 1 (FADH₂) = 9

3. Beta-Oxidation of Fatty acids - c,e

emulsification of TAG a,b

fatty acid synthesis- d

formation of chylomicrons-a

formation of micelles-a,b

formation of fatty Acyl CoA -d,e

4. b. Activated fatty acids must be transported into a matrix for beta-oxidation. if the carnitine shuttle fails, then the Beta-Oxidation is impaired.