Chapter 12 Self-test questions

. Which of the following statements about nicotinamide adenine dinucleotide (NAD⁺) is correct?

NAD⁺ is the initial electron donor in many metabolic oxidation reactions.

NADH is the initial electron acceptor in many metabolic oxidation reactions.

NAD⁺ is the initial electron acceptor in many metabolic oxidation reactions.

NAD⁺ is a prosthetic group for several dehydrogenases.

. Which of the following statements about flavin adenine dinucleotide (FAD) is correct?

FAD is a coenzyme for specific dehydrogenases.

FAD is derived from riboflavin, a B-group vitamin (vitamin B₂).

FADH₂ can accept two electrons acting as an electron carrier.

FAD can also be an electron donor.

. Which of the following statements about glycolysis is correct?

Glycolysis requires oxygen since it is involved in the oxidation of glucose.

The end products of glycolysis are always pyruvate and ATP.

The end products of glycolysis are always lactate and ATP.

Although glycolysis is a stage in the oxidation of glucose it can occur anaerobically.

. Which of the following statements about the enzyme lactate dehydrogenase is correct?

Lactate dehydrogenase catalyses the oxidation of pyruvate to lactate to regenerate NAD⁺.

Lactate dehydrogenase catalyses the reduction of pyruvate to lactate to regenerate NAD⁺.

Lactate dehydrogenase catalyses the reduction of pyruvate to lactate to regenerate NADH.

Lactate dehydrogenase ensures mitochondrial NADH is oxidised.

. Which of the following statements about mitochondria is correct?

The oxidation of the NADH and FADH₂produced in the citric acid cycle occurs in the mitochondrial matrix.

The outer mitochondrial membrane is invaginated and forms cristae to increase its capacity for ATP generation.

The inner mitochondrial membrane is relatively permeable to most solutes.

The inner mitochondrial membrane is relatively impermeable to most solutes.

. Which of the following reactions constitutes an 'oxidative decarboxylation'?

The conversion of pyruvate into acetyl CoA.

The conversion of pyruvate into oxaloacetate.

The conversion of lactate into pyruvate.

The conversion of pyruvate into lactate.

. Which of the following statements is/are true regarding the metabolism of acetyl Co A?

It can be converted into pyruvate.

It can be converted into ketone bodies.

It can be oxidised in the TCA cycle.

It can be converted into cholesterol.

. What type of molecule is NAD+?

A cofactor.

A coenzyme.

A prosthetic group.

A vitamin.

. What is achieved by anaerobic glycolysis in the erythrocyte?

Regeneration of NAD⁺.

Regeneration of FAD.

Production of 4 ATP molecules.

Production of Acetyl CoA.

. Which enzyme is involved in the oxidative decarboxylation of pyruvate to acetyl coenzyme A?

Pyruvate decarboxylase.

Pyruvate dehydrogenase.

Pyruvate kinase.

Lactate dehydrogenase.

. Fatty acids and glucose have very different structures but have a common pathway of complete oxidation. What is the first common metabolite in their oxidation pathways?

Acetoacetyl CoA.

Citrate.

Malonyl CoA.

Acetyl-CoA.

. Which of the statements shown below regarding amino acid metabolism is/are true?

Amino acids can be converted into pyruvate.

Amino acids can be converted into acetyl-CoA.

Amino acids can be converted into oxaloacetate.

Amino acids can be converted into 2 oxoglutarate.

Chapter 12 Self-test questions

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