AP Biologymediummcq1 pt
Why does fermentation occur when oxygen is absent?
A.To regenerate NAD⁺ so glycolysis can continue
B.To make extra ATP beyond glycolysis
C.To produce oxygen for the cell
D.To store glucose as glycogen
Explanation
Core Concept
Fermentation oxidizes NADH back to NAD⁺ (making lactate or ethanol), letting glycolysis keep producing its 2 ATP per glucose when respiration is impossible.
Correct Answer
ATo regenerate NAD⁺ so glycolysis can continue
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