Biology

Cellular Respiration and Enzymes

1,551 Questions

Explore key concepts of cellular respiration, including glycolysis, the Krebs cycle, and the electron transport chain. These questions also cover ATP production, anaerobic respiration, and essential metabolic pathways. This topic forms a core part of the biology syllabus for many competitive examinations.

Glycolysis and metabolic pathwaysKrebs cycle processesElectron transport chainATP production countAnaerobic respiration products

Cellular Respiration and Enzymes Questions

Multiple choice

What is the name of the molecule that carries high-energy electrons from glycolysis and the Krebs cycle to the electron transport chain?

  1. NADH

  2. FADH2

  3. ATP

  4. ADP
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

NADH is the molecule that carries high-energy electrons from glycolysis and the Krebs cycle to the electron transport chain. It is produced during the oxidation of glucose and other organic molecules.

Multiple choice

Which of the following is the name of the enzyme that catalyzes the conversion of pyruvate to acetyl-CoA?

  1. Pyruvate dehydrogenase

  2. Citrate synthase

  3. Aconitase

  4. Isocitrate dehydrogenase
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Pyruvate dehydrogenase is the enzyme that catalyzes the conversion of pyruvate to acetyl-CoA. This reaction is the first step of the Krebs cycle.

Multiple choice

Which of the following is the name of the enzyme that catalyzes the conversion of isocitrate to α-ketoglutarate?

  1. Isocitrate dehydrogenase

  2. Aconitase

  3. Succinate dehydrogenase

  4. Fumarase
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Isocitrate dehydrogenase is the enzyme that catalyzes the conversion of isocitrate to α-ketoglutarate. This reaction is the second step of the Krebs cycle.

Multiple choice

Which of the following is the name of the enzyme that catalyzes the conversion of succinate to fumarate?

  1. Succinate dehydrogenase

  2. Fumarase

  3. Malate dehydrogenase

  4. Citrate synthase
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Succinate dehydrogenase is the enzyme that catalyzes the conversion of succinate to fumarate. This reaction is the fourth step of the Krebs cycle.

Multiple choice

Which of the following is the name of the enzyme that catalyzes the conversion of fumarate to malate?

  1. Fumarase

  2. Malate dehydrogenase

  3. Citrate synthase

  4. Aconitase
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Fumarase is the enzyme that catalyzes the conversion of fumarate to malate. This reaction is the fifth step of the Krebs cycle.

Multiple choice

Which of the following is the name of the enzyme that catalyzes the conversion of malate to oxaloacetate?

  1. Malate dehydrogenase

  2. Citrate synthase

  3. Aconitase

  4. Isocitrate dehydrogenase
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Malate dehydrogenase is the enzyme that catalyzes the conversion of malate to oxaloacetate. This reaction is the sixth and final step of the Krebs cycle.