Question

Which of the following statements is incorrect about the breakdown of respiratory substrates under anaerobic conditions?

• A. Net gain of water molecules is not zero.
• B. Pyruvic acid undergoes oxidation decarboxylation
• C. Incomplete breakdown of respiratory substrate in germinating seeds
• D. Formation of alcohol by yeast

Answer 1

The correct option is A Net gain of water molecules is not zero.

• Respiration that occurs in the absence of oxygen is called anaerobic respiration. It occurs in two steps, glycolysis and fermentation.
• In glycolysis, one glucose molecule splits into two pyruvic acid molecules.
• Pyruvic acid undergoes oxidative decarboxylation to form acetaldehyde which will later convert into ethyl alcohol.
• In this whole process net gain of water is zero.

So, the correct answer is option A.