Question

1. Select the TRUE statement about the citric acid cycle.

A. Isocitrate dehydrogenase is a multienzyme complex that is very similar to the pyruvate dehydrogenase complex

B. The two decarboxylation steps occur right after each other, first via oxidative alpha- decarboxylation, then via oxidative beta- decarboxylation.

C. In one turn of the cycle, the two carbons that enter the cycle as acetyl CoA are the same two carbons that are released as CO2.

D. A flavin containing dehydrogenase enzymes oxidizes a C-C single bond into a C=C double bond

E. Three dehydrogenase enzymes oxidize an alcohol ROH into a C=O double bond

2. Select the TRUE statement about the component of the electron transport chain.

A. Complex III is a peripheral membrane protein

B. Cytochrome c is a lipid-linked protein

C. Complex II is a transmembrane protein

D. Complex I is an integral membrane protein

E. Complex IV is not a transmembrane protein

3. The rate of oxygen consumption at the inner mitochondrial membrane is related to all the following EXCEPT:

A. Availability of ADP in the mitochondria

B. The rate of ATP phosphorylation to ADP

C. The availability of NADH and FADH2 in the mitochondria.

D. The rate of the citric acid cycle

E. The rate of O2 delivery to the mitochondria

3. The β-Oxidation of hexanoic CoA (6:0) yields:

A. 6 Acetyl-CoA + 6 FADH2 + 6 NADH

B. 6 Acetyl-CoA + 7 FADH + 6 NAD+

C. 6 Acetyl-CoA + 5 FADH2 + 5 NADH

D. 5 Acetyl-CoA + 5 FADH2 + 5 NADH

E. 5 Acetyl-CoA + 6 FADH2 + 6 NADH

Answer 1

1.

Ans. (D) Flavin containing dehydrogenase enzyme and it oxidizes the single carbon bond into double carbon bond.

Succinate dehydrogenase is the enzyme having flavin dinucleotide as the coenzyme. Enzyme causes the removal of the two hydrogen atoms from the succinate which are added to the Flavin dinucleotide and a molecule of fumarate is produced.