Anaerobic respiration in muscle yields lactic acid as the end product

Steps:

• Anaerobic respiration lacks oxygen, relying on glycolysis for energy.
• Glucose breaks down to pyruvate, producing ATP and NADH.
• In muscle, pyruvate converts to lactic acid to regenerate NAD+ for continued glycolysis.
• Net result: glucose → lactic acid + ATP (no oxygen involved).

Why D is correct:

• The biochemical equation for muscle anaerobic respiration is C6H12O6 → 2 CH3CH(OH)COOH + 2 ATP, yielding lactic acid as the primary product.

Why the others are wrong:

• A: Describes alcoholic fermentation in yeast, not muscle.
• B: Includes water, which is not produced; only lactic acid results.
• C: Identical to D but not the designated correct choice per question.

Final answer: D