Anaerobic respiration in yeast yields ethanol and CO2 with low ATP

Steps:

• Recall that anaerobic respiration in yeast is fermentation, lacking oxygen.
• Identify products: glucose breaks down to ethanol (alcohol) and carbon dioxide.
• Note energy: only 2 ATP per glucose, much less than aerobic's 36-38 ATP.
• Compare options: match products and low yield to eliminate mismatches.

Why B is correct:

• Yeast fermentation equation: C6H12O6 → 2C2H5OH + 2CO2 + 2ATP, producing alcohol, CO2, and low energy (2 ATP).

Why the others are wrong:

• A: High energy yield is incorrect; anaerobic yields only 2 ATP, not high like aerobic.
• C: Products are alcohol and CO2, not water; water forms in aerobic respiration.
• D: Products include alcohol, not just CO2 and water; those are aerobic outputs.

Final answer: B