Biology

Cellular Respiration and Enzymes

1,721 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 enzyme that catalyzes the conversion of inosine to hypoxanthine?

  1. Inosine deaminase

  2. Inosine kinase

  3. Inosine phosphorylase

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

Inosine deaminase catalyzes the conversion of inosine to hypoxanthine.

Multiple choice

Which enzyme catalyzes the conversion of adenosine to inosine?

  1. Adenosine deaminase

  2. Adenosine kinase

  3. Adenosine phosphorylase

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

Adenosine deaminase catalyzes the conversion of adenosine to inosine.

Multiple choice

What is the name of the enzyme that catalyzes the conversion of guanosine to guanine?

  1. Guanosine deaminase

  2. Guanosine kinase

  3. Guanosine phosphorylase

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

Guanosine deaminase catalyzes the conversion of guanosine to guanine.

Multiple choice

Which enzyme catalyzes the conversion of xanthine to hypoxanthine?

  1. Xanthine oxidase

  2. Xanthine deaminase

  3. Xanthine kinase

  4. Xanthine phosphorylase
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Xanthine deaminase catalyzes the conversion of xanthine to hypoxanthine.

Multiple choice

What is the name of the enzyme that catalyzes the conversion of uric acid to allantoin?

  1. Uricase

  2. Allantoinase

  3. Allantoin kinase

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

Uricase catalyzes the conversion of uric acid to allantoin.

Multiple choice

Which enzyme catalyzes the conversion of allantoin to glyoxylate and urea?

  1. Allantoinase

  2. Allantoin kinase

  3. Allantoin phosphorylase

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

Allantoinase catalyzes the conversion of allantoin to glyoxylate and urea.

Multiple choice

Which of the following is the first stage of cellular respiration?

  1. Glycolysis

  2. Krebs Cycle

  3. Electron Transport Chain

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

Glycolysis is the first stage of cellular respiration, where glucose is broken down into pyruvate.

Multiple choice

What is the net gain of ATP molecules during glycolysis?

  1. 2

  2. 4

  3. 6

  4. 8
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

During glycolysis, 2 molecules of ATP are produced and 2 molecules of ATP are consumed, resulting in a net gain of 2 ATP molecules.

Multiple choice

Which of the following is a product of glycolysis?

  1. Pyruvate

  2. Acetyl CoA

  3. NADH

  4. FADH2
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Pyruvate is one of the products of glycolysis, along with NADH and ATP.

Multiple choice

What is the role of pyruvate dehydrogenase in cellular respiration?

  1. Converts pyruvate to acetyl CoA

  2. Generates NADH and FADH2

  3. Produces ATP through oxidative phosphorylation

  4. Regulates the Krebs Cycle
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Pyruvate dehydrogenase is an enzyme that converts pyruvate to acetyl CoA, which then enters the Krebs Cycle.

Multiple choice

How many molecules of ATP are produced during the Krebs Cycle?

  1. 2

  2. 4

  3. 6

  4. 8
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

During the Krebs Cycle, 2 molecules of ATP are produced per molecule of acetyl CoA.

Multiple choice

Which of the following is a product of the Krebs Cycle?

  1. Pyruvate

  2. Acetyl CoA

  3. NADH

  4. FADH2
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

NADH is one of the products of the Krebs Cycle, along with FADH2, ATP, and carbon dioxide.

Multiple choice

What is the role of the electron transport chain in cellular respiration?

  1. Generates ATP through oxidative phosphorylation

  2. Produces NADH and FADH2

  3. Converts pyruvate to acetyl CoA

  4. Regulates the Krebs Cycle
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The electron transport chain is responsible for generating ATP through oxidative phosphorylation, using the energy released from the transfer of electrons.

Multiple choice

How many molecules of ATP are produced during oxidative phosphorylation?

  1. 2

  2. 4

  3. 6

  4. 32
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

During oxidative phosphorylation, approximately 32 molecules of ATP are produced per molecule of glucose.

Multiple choice

Which of the following is the final electron acceptor in the electron transport chain?

  1. Oxygen

  2. NADH

  3. FADH2

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

Oxygen is the final electron acceptor in the electron transport chain, and its reduction to water is coupled with the generation of ATP.