Question

Production of alcohol by yeast fermentation is
A. Anaerobic
B. Aerobic
C. Light dependent
D. Both A and C

Answer 1

Hint: Fermentation is a process in which the organic food material gets converted into alcohol by the action of some microorganisms such as Yeast.

Complete Answer:
- Alcoholic fermentation is a biological process which is carried out by certain kinds of microorganisms like Yeast and certain bacteria. These microorganisms convert organic food material into the alcohol and carbon dioxide as a by-product in anaerobic condition.
- Anaerobic means the absence of Oxygen. Anaerobic process also takes place in some species of fish where it provides energy under the scarce of Oxygen.
- Alcoholic fermentation begins with the glycolysis (breakdown of sugar molecules ) that results in two molecules of pyruvate.
- These two molecules of pyruvate under anaerobic condition are first converted to a midway molecule which is acetaldehyde.
- Acetaldehyde further releases carbon dioxide and gets converted into two molecules of ethanol (alcohol).

Uses of alcoholic fermentation:
- Used for making bakery products like bred, cake, etc. In this when yeast and dough combine with each other, yeast breaks down the sugar and gives off carbon dioxide which causes the bread to rise.
- Used for the production of alcoholic beverages like wine from fruit juices and beer from grains.
- Used to flavor or preserve many dairy products such as yogurt and vegetables.

Hence, option A is the correct option for this question.

Note: If there will be no anaerobic condition which means there will be oxygen present then the species of yeast convert the sugars completely into carbon dioxide and water. There will be no production of alcohol in this condition.