Mitochondrial Bioenergetics

Question 1

Which is the high energy bond in Acetyl-CoA located?
A. S-CoA
B. CH3-C
C. C=O
D. S-C=O

Answer 1

A. S-CoA

Question 2

Why should Ala intake be restricted in PDC deficiency?
A. Ala produces acetyl-CoA which cannot be processed
B. Ala is converted to pyruvate via transamination reaction
C. Ala replenishes Fumarate
D. Ala replenishes Succinyl CoA

Answer 2

B. Ala is converted to pyruvate via transamination reaction

Question 3

Where does the substrate level phosphorylation produce a high energy substance?
A. Isocitrate –> alpha-ketoglutarate + NADH + H+
B. A-Ketoglutarate –> succinyl-CoA + NADH + H+
C. Succinate –> Fumarate + FADH2
D. Succinyl-CoA –> Succinate + GTP
E. Malate –> Oxaloacetate + NADH + H+

Answer 3

D. Succinyl-CoA –> Succinate + GTP

Question 4

How many moles of ATP is generated from 1 mole of glucose oxidized via TCA cycle?
A. 10 mol ATP
B. 20 mol ATP
C. 36 mol ATP
D. 18 mol ATP
E. 15 mol ATP

Answer 4

B. 20 mol ATP (2x10 mol)

Question 5

Which of the following factors governs the proton motive force (pmf)?
A. Standard redox potential of the OxPhos intermediates
B. ATP production ratio
C. Membrane potential and pH gradient
D. Proton gradient formation in intermembrane space

Answer 5

C. Membrane potential and pH gradient

Question 6

Where does the OxPhos reaction cascade take place?
A. Outer membrane
B. Cytosol
C. Inner membrane
D. Matrix
E. Intermembrane space

Answer 6

C. Inner membrane

Question 7

In the well fed state, which of the following reactions is involved in the transport of NADH from the cytosol into the mitochondria?
A. Active transport coupled with hydrolysis of ATP
B. Conversion of lactate to pyruvate
C. Diffusion of protons into mitochondria
D. Malate shuttle

Answer 7

D. Malate shuttle