Biochemistry quiz

Which of the following enzymes catalyzes the first committed step of glycolysis?

• Hexokinase

• Glucokinase

• Phosphofructokinase-1 (PFK-1)

• Pyruvate kinase

Which of the following enzymes is involved in substrate-level phosphorylation in glycolysis?

• Enolase

• Aldolase

• Glyceraldehyde-3-phosphate dehydrogenase

• Pyruvate kinase

Which step in glycolysis produces NADH?

• Hexokinase reaction

• Phosphofructokinase-1 reaction

• Glyceraldehyde-3-phosphate dehydrogenase reaction

• Pyruvate kinase reaction

In anaerobic conditions, pyruvate is converted to:

• Acetyl-CoA

• Lactate

• Oxaloacetate

• Ethanol only

Which of the following steps in glycolysis is irreversible under physiological conditions?

• Triose phosphate isomerase reaction

• Glyceraldehyde-3-phosphate dehydrogenase reaction

• Phosphoglycerate kinase reaction

• Phosphofructokinase-1 reaction

Which coenzyme is required for the oxidation of glyceraldehyde-3-phosphate in glycolysis?

• NAD⁺

• FAD

• NADP⁺

• TPP

The enzyme enolase in glycolysis catalyzes the conversion of:

• 3-phosphoglycerate to 2-phosphoglycerate

• 2-phosphoglycerate to phosphoenolpyruvate

• Fructose-6-phosphate to fructose-1,6-bisphosphate

• Pyruvate to lactate

The pyruvate dehydrogenase complex converts pyruvate into:

• Oxaloacetate

• Lactate

• Acetyl-CoA

• Citrate

Which of the following is NOT a coenzyme required by the PDH complex?

• Thiamine pyrophosphate (TPP)

• Biotin

• NAD⁺

• Lipoic acid

The E1 component of the PDH complex catalyzes:

• Decarboxylation of pyruvate

• Transfer of acetyl group to CoA

• Regeneration of oxidized lipoamide

• Reduction of NAD⁺