Anaerobic metabolism is more efficient than aerobic metabolism.

• A. True
• B. It depends on the cell type
• C. False
• D. It is never used

Answer: (C)

Energy efficiency here refers to how much ATP you can get from one molecule of glucose. Aerobic metabolism uses oxygen to fully oxidize glucose through glycolysis, the TCA cycle, and oxidative phosphorylation, yielding about 30–32 ATP per glucose. Anaerobic metabolism relies on glycolysis alone and, even with fermentation to regenerate NAD+, produces only about 2 ATP per glucose. So anaerobic pathways provide energy quickly but far less total energy per glucose. This is why the statement is not correct: aerobic metabolism is more efficient in terms of ATP yield.