Question

In alcoholic fermentation, yeast _______.

1) turns congeners into alcohol
2) activates enzymes that decrease the level of acid in the ferment
3) prevents bacteria from attacking germinated grains
4) consumes sugar and produces ethyl alcohol, carbon dioxide, and heat

Answer 1

In alcoholic fermentation, yeast consumes sugar and produces ethyl alcohol, carbon dioxide, and heat. The process involves decarboxylation of pyruvate to acetaldehyde, followed by reduction to ethanol, and is used in making bread, beer, wine, and biofuels.

Step-by-step explanation:

In alcoholic fermentation, yeast consumes sugar and produces ethyl alcohol, carbon dioxide, and heat. The process involves two key reactions. Firstly, the enzyme pyruvate decarboxylase removes a carboxyl group from pyruvate to produce acetaldehyde and release CO2.

This reaction is assisted by a coenzyme derived from vitamin B1 (thiamine). In the subsequent step, alcohol dehydrogenase catalyzes the reduction of acetaldehyde to ethanol, regenerating NAD+ from NADH in the process. This allows glycolysis to continue making ATP. The chemical reaction for the fermentation of glucose can be described as: C6H12O6 (glucose) → 2 C2H5OH (ethanol) + 2 CO2 (carbon dioxide). This is significant in the production of bread, beer, wine, and biofuels.