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
What is the role of the Krebs cycle in cellular respiration?
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To break down pyruvate into acetyl-CoA
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To produce ATP
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To generate NADH and FADH2
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To release carbon dioxide
A
Correct answer
Explanation
The Krebs cycle is the process of breaking down pyruvate into acetyl-CoA, which is then used to produce ATP.
What is the role of oxidative phosphorylation in cellular respiration?
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To break down glucose into pyruvate
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To produce ATP
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To generate NADH and FADH2
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To release carbon dioxide
B
Correct answer
Explanation
Oxidative phosphorylation is the process of producing ATP from NADH and FADH2.
What is the net gain of ATP from one molecule of glucose during cellular respiration?
C
Correct answer
Explanation
The net gain of ATP from one molecule of glucose during cellular respiration is 38.
What is the role of NADH and FADH2 in cellular respiration?
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To carry electrons
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To produce ATP
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To generate NAD+ and FAD
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To release carbon dioxide
A
Correct answer
Explanation
NADH and FADH2 carry electrons from glycolysis and the Krebs cycle to the electron transport chain.
What is the role of the electron transport chain in cellular respiration?
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To break down glucose into pyruvate
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To produce ATP
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To generate NADH and FADH2
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To release carbon dioxide
B
Correct answer
Explanation
The electron transport chain is the process of producing ATP from NADH and FADH2.
What is the role of ATP in cellular respiration?
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To break down glucose into pyruvate
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To produce ATP
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To generate NADH and FADH2
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To release carbon dioxide
Correct answer
Explanation
ATP is the energy currency of the cell and is used to power cellular processes.
What is the role of carbon dioxide in cellular respiration?
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To break down glucose into pyruvate
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To produce ATP
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To generate NADH and FADH2
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To release carbon dioxide
D
Correct answer
Explanation
Carbon dioxide is a waste product of cellular respiration and is released from the cell.
What is the role of water in cellular respiration?
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To break down glucose into pyruvate
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To produce ATP
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To generate NADH and FADH2
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To release carbon dioxide
Correct answer
Explanation
Water participates in the Krebs cycle, where it is used to form acetyl-CoA.
What is the role of oxygen in cellular respiration?
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To break down glucose into pyruvate
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To produce ATP
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To generate NADH and FADH2
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To release carbon dioxide
Correct answer
Explanation
Oxygen participates in oxidative phosphorylation, where it is used to accept electrons from the electron transport chain.
What is the role of mitochondria in cellular respiration?
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To break down glucose into pyruvate
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To produce ATP
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To generate NADH and FADH2
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To release carbon dioxide
Correct answer
Explanation
Mitochondria house the Krebs cycle and oxidative phosphorylation, which are the two main stages of cellular respiration.
What is the role of the cytosol in cellular respiration?
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To break down glucose into pyruvate
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To produce ATP
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To generate NADH and FADH2
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To release carbon dioxide
Correct answer
Explanation
The cytosol houses glycolysis, which is the first stage of cellular respiration.
What is the role of the plasma membrane in cellular respiration?
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To break down glucose into pyruvate
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To produce ATP
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To generate NADH and FADH2
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To release carbon dioxide
Correct answer
Explanation
The plasma membrane transports glucose and oxygen into the cell, which are necessary for cellular respiration.
What is the role of the mitochondrial membrane in energy production?
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It generates ATP through oxidative phosphorylation
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It transports electrons along the electron transport chain
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It pumps protons across the membrane, creating a proton gradient
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All of the above
D
Correct answer
Explanation
The mitochondrial membrane is a double membrane that plays a key role in energy production. It generates ATP through oxidative phosphorylation, transports electrons along the electron transport chain, and pumps protons across the membrane, creating a proton gradient.
What is the term for the energy system that provides ATP for muscle contractions during short-duration, high-intensity activities?
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Aerobic system
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Anaerobic alactic system
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Anaerobic glycolytic system
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Oxidative phosphorylation system
B
Correct answer
Explanation
The anaerobic alactic system is the energy system that provides ATP for muscle contractions during short-duration, high-intensity activities, such as sprinting or weightlifting. It does not require oxygen and relies on the breakdown of stored creatine phosphate.
What is the term for the process by which the body produces energy from food?
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Metabolism
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Glycolysis
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Krebs cycle
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Electron transport chain
A
Correct answer
Explanation
Metabolism is the process by which the body produces energy from food. It involves a series of chemical reactions that break down food molecules and convert them into energy that can be used by the body's cells.