Question

The product obtained by the anaerobic respiration of yeast is:
A) Lactic acid
B) Pyruvic acid
C) Ethanol
D) Acetic acid

Answer 1

Hint: Yeasts are Eukaryotic microorganisms. They are unicellular organisms. Yeast can have sexual and asexual reproductive cycles. The yeast uses cellular respiration. The Fermentation is used by yeast which is anaerobic respiration.

Complete Answer:
- Anaerobic respiration is the process of respiration which happens in the absence of oxygen.
- The yeast has both modes of respiration aerobic as well as anaerobic respiration.
- Fermentation is a type of anaerobic respiration which is used by yeast.
- Fermentation is defined as a metabolic process in which energy is obtained from carbohydrates in the absence of oxygen.
- The yeast converts the sugar into alcohol.
- The breakdown of sugars by yeast to form pyruvate molecules is called glycolysis.
- The end product is obtained by anaerobic respiration of yeast are ethyl alcohol and carbon dioxide.
- The Fermentation is used to produce ATP anaerobically.
- In the yeasts, the end products ethanol and carbon dioxide are formed which can be used in food processing.
- The yeast can convert carbohydrates into energy in both aerobic as well as anaerobic conditions.

So the correct answer is Ethanol.

Note: The end products are used. The carbon dioxide is used in the processing of bread. The ethanol is used as an intoxicating agent in alcoholic beverages. The breakdown of pyruvic acid from glucose into ethanol and carbon dioxide is done by the yeast. The most common yeast used in the process of fermentation is Saccharomyces Cerevisiae.