Final answer:
The difference between aerobic and anaerobic respiration lies in the oxygen requirement, where aerobic respiration requires oxygen and produces more ATP, while anaerobic respiration does not require oxygen but produces less ATP.
Step-by-step explanation:
The main difference between aerobic respiration and anaerobic respiration is A) Oxygen requirement. Aerobic respiration requires oxygen to break down glucose or other nutrients to produce carbon dioxide, water, and a high amount of ATP, up to 38 molecules per glucose molecule. This process is highly efficient and takes place in the mitochondria. Anaerobic respiration occurs in the absence of oxygen and relies on other compounds as electron acceptors. It only utilizes glycolysis for ATP production, which results in just 2 ATP molecules per glucose molecule, along with byproducts like lactate or ethanol in different types of fermentation. The energy produced without oxygen is significantly less compared to aerobic conditions, leading to less power, which is the rate of free-energy production.