Questions and answers for exam Preparation

MCQs

Total Questions : 211 | Page 4 of 22 pages

Question 31. Protein that contains a nucleic acid derivative of riboflavin is called _________

Nucleic acid
Amino acid
Flavoprotein
None of the mentioned

Discuss Question

Answer: Option C. -> Flavoprotein
Answer: (c).Flavoprotein

Question 32. The only membrane bound enzyme in the citric acid cycle is _________

Succinate dehydrogenase
NADH dehydrogenase
ATP synthase
Acyl co-A dehydrogenase

Discuss Question

Answer: Option A. -> Succinate dehydrogenase
Answer: (a).Succinate dehydrogenase

Question 33. A lipid-soluble benzoquinone with a long isoprenoid side chain is?

Ubiquinone
Cytochrome b
Cytochrome c
Cytochrome a

Discuss Question

Answer: Option A. -> Ubiquinone
Answer: (a).Ubiquinone

Question 34. The first step in the β oxidation of fatty acyl co-A is catalyzed by _________

Succinate dehydrogenase
NADH dehydrogenase
ATP synthase
Acyl co-A dehydrogenase

Discuss Question

Answer: Option D. -> Acyl co-A dehydrogenase
Answer: (d).Acyl co-A dehydrogenase

Question 35. NADP-linked dehydrogenase catalyzes _________

Glucose 6-phosphate+NADP⁺ ↔ 6-phosphogluconate + NADPH + H⁺
Lactate + NAD⁺ ↔ pyruvate + NADH + H⁺
Pyruvate + CoA + NAD⁺ ↔ acetyl-CoA + CO₂ + NADH + H⁺
L-Malate + NAD⁺ ↔ oxaloacetate + NADH + H⁺

Discuss Question

Answer: Option A. -> Glucose 6-phosphate+NADP⁺ ↔ 6-phosphogluconate + NADPH + H⁺
Answer: (a).Glucose 6-phosphate+NADP⁺ ↔ 6-phosphogluconate + NADPH + H⁺

Question 36. Which of the following is the prosthetic group of NADH dehydrogenase?

NADH
FAD
NADPH
FMN

Discuss Question

Answer: Option D. -> FMN
Answer: (d).FMN

Question 37. If the oxidative phosphorylation was uncoupled in the mitochondria then there is a/an

Decreased concentration of ADP in the mitochondria
Decreased oxidative rate
Increased inorganic phosphate in the mitochondria
Decreased production of heat

Discuss Question

Answer: Option C. -> Increased inorganic phosphate in the mitochondria
Answer: (c).Increased inorganic phosphate in the mitochondria

Question 38. If 2, 4-dinitrophenol is added to tightly coupled mitochondria that are actively oxidizing succinate

Electron flow will continue but ATP synthesis will not occur
Electron flow will continue but ATP synthesis will be increased
Electron flow will cease but ATP synthesis will continue
Both electron flow and ATP synthesis will be ceased

Discuss Question

Answer: Option A. -> Electron flow will continue but ATP synthesis will not occur
Answer: (a).Electron flow will continue but ATP synthesis will not occur

Question 39. If mitochondria were blocked at the site of NADH oxidation and were treated with succinate as substrate, what would the P : O ratio is?

Same as that normally produced by succinate
One more than normally produced by succinate
One less than normally produced by succinate
Zero

Discuss Question

Answer: Option A. -> Same as that normally produced by succinate
Answer: (a).Same as that normally produced by succinate

Question 40. Effect of valinomycin on oxidative phosphorylation does not involve

pH gradient across the inner mitochondrial membrane decreases
Rate of flow of electrons increases
Rate of oxygen consumption increases
Net yield of ATP decreases

Discuss Question

Answer: Option A. -> pH gradient across the inner mitochondrial membrane decreases
Answer: (a).pH gradient across the inner mitochondrial membrane decreases