Question

unit 3 test.m
3.1.9-12.g which of the following best explains why aerobic respiration is more energy efficient than anaerobic respiration?
aerobic respiration occurs in one step, while anaerobic respiration requires several steps.
aerobic respiration fully breaks down glucose, while anaerobic respiration does not.
aerobic respiration produces more atp per molecule of glucose.

Explanation:

1. Analyze the first option: Both aerobic and anaerobic respiration have multiple steps (aerobic has glycolysis, Krebs cycle, ETC; anaerobic has glycolysis and fermentation), so this is incorrect.
2. Analyze the second option: While aerobic fully breaks down glucose and anaerobic does not, the key to energy efficiency is ATP production. This is a contributing factor but not the best explanation of "energy efficiency" (which is about ATP yield).
3. Analyze the third option: Aerobic respiration produces about 36 - 38 ATP per glucose, while anaerobic produces 2 ATP per glucose. The higher ATP yield per glucose molecule directly explains why aerobic is more energy - efficient.

Answer:

Aerobic respiration produces more ATP per molecule of glucose.