Question

level 5
q3
what molecule is produced during the
fermentation of yeast?
a. pyruvic acid
b. lactic acid
c. methanol
d. ethanol
diagram showing fermentation pathway with glucose, adp, atp, nad+, nadh, pyruvate, acetaldehyde, co₂, and other molecules
a. pyruvic acid
b. lactic acid
c. methanol
d. ethanol

Explanation:

Yeast fermentation (alcoholic fermentation) converts pyruvate into ethanol and carbon dioxide. Pyruvic acid is a product of glycolysis (before fermentation), lactic acid is from lactic acid fermentation (e.g., in muscle cells or some bacteria), and methanol is not a product of yeast fermentation. So the correct molecule produced is ethanol.

Answer:

D. Ethanol