Which of the following best explains why aerobic energy supply can be sustained for hours during cellular respiration?

• A. Aerobic respiration quickly depletes glucose stores, limiting its duration.
• B. Aerobic respiration relies solely on glycolysis, which is a rapid but short-term energy source.
• C. Aerobic respiration produces large amounts of ATP using oxygen, allowing prolonged energy supply.
• D. Aerobic respiration does not require oxygen and therefore can continue indefinitely.

Answer: (C)

Verified step by step guidance

1. Step 1: Begin by understanding the concept of aerobic respiration. Aerobic respiration is a metabolic process in which cells use oxygen to convert glucose into ATP, the energy currency of the cell. This process occurs in the mitochondria and is highly efficient, producing large amounts of ATP.
2. Step 2: Compare aerobic respiration to glycolysis. Glycolysis is an anaerobic process that occurs in the cytoplasm and produces a small amount of ATP quickly, but it is not sustainable for long periods because it does not use oxygen and relies on limited glucose stores.
3. Step 3: Analyze the role of oxygen in aerobic respiration. Oxygen acts as the final electron acceptor in the electron transport chain, allowing the complete oxidation of glucose and the production of large amounts of ATP. This makes aerobic respiration sustainable for extended periods.
4. Step 4: Evaluate the statement 'Aerobic respiration produces large amounts of ATP using oxygen, allowing prolonged energy supply.' This is correct because the presence of oxygen enables the efficient production of ATP, which supports sustained energy supply during activities like endurance exercise.
5. Step 5: Eliminate incorrect options. For example, 'Aerobic respiration does not require oxygen' is false because oxygen is essential for aerobic respiration. Similarly, 'Aerobic respiration quickly depletes glucose stores' is incorrect because glucose is used efficiently in aerobic respiration, and 'Aerobic respiration relies solely on glycolysis' is false because glycolysis is only the first step in the process.