Asked in Premeth past paper pool — BiologyModerate

The given diagram summarises the reactions of anaerobic respiration:

Correct answer: B. B.

  • A. A.
  • B. B.
  • C. C.
  • D. D.

Explanation

The correct answer is the formation of pyruvic acid from glucose. This step is known as glycolysis, which is the initial stage of both aerobic and anaerobic respiration. During glycolysis, glucose is broken down into two molecules of pyruvate, and ATP is produced. In anaerobic conditions, pyruvate can be further converted into either ethanol or lactic acid, but these subsequent steps do not produce ATP. Therefore, the only stage in anaerobic respiration where ATP is generated is during the formation of pyruvic acid from glucose.

Last updated

About Cellular Respiration

Cellular respiration releases energy from glucose through glycolysis, the link reaction, the Krebs cycle and the electron transport chain, producing ATP. The pathway differs in oxygen availability: aerobic respiration uses oxygen and yields more ATP, while anaerobic respiration produces much less ATP and forms lactic acid in muscles or ethanol and carbon dioxide in yeast.

Practise Bioenergetics

1,378 free Bioenergetics MCQs from Biology, each with the correct answer and an explanation. Unlimited attempts, no account needed.

Exams that ask Biology questions like this

Biology is on 6 papers prepared for on TestUstad, and all of them draw the same bank, so this question is worth knowing for every one of them.

Related questions