Question

Following compound in the process of alcoholic fermentation is a 2 carbon compounds, except

• A. ethanol
• B. formaldehyde
• C. pyruvate
• D. ethyl alcohol

Answer 1

The correct option is C pyruvate

Alcoholic fermentation or ethanol fermentation is a biological process by which sugar is converted into alcohol and carbon dioxide. In the process of breaking down glucose into smaller constituents energy is released. The glucose is broken into two 3C compounds i.e. pyruvate/pyruvic acid. In the process of alcoholic fermentation, this 3C compound pyruvate is decarboxylated into a 2C compound called acetaldehyde, releasing CO${}_2$ as a by-product with the help of enzyme pyruvate decarboxylase. Acetaldehyde in turn with the help of another enzyme alcohol dehydrogenase along with coenzyme NADH gets converted to ethanol or ethyl alcohol, a 2C compound.
So among the options only pyruvate is a 3C compound while rest ethanol/ethyl acohol and formaldehyde are 2C compounds.