Question

Which of the following is true about Krebs cycle?

• A. GTP / ATP is formed
• B. Decarboxylation
• C. Acetyl CoA acceptor is OAA
• D. All of the above

Answer 1

The correct option is D All of the above

Citric acid cycle completely metabolises acetyl CoA. Glycolysis produces two molecules of pyruvic acid from one molecule of glucose. Two molecules of pyruvic acid (each containing three carbon atoms) are oxidatively decarboxylated into two molecules of acetyl CoA (each containing two carbon atoms). These acetyl CoA molecules are metabolised by two turns of Krebs cycle. In the first reaction of Krebs cycle, acetyl CoA reacts with oxaloacetic acid to form citric acid. Two carbon atoms, which enter the citric acid cycle are released as two molecules of carbon dioxide in two successive decarboxylation reactions during the course of Krebs cycle. GTP is synthesized through substrate level phosphorylation during Krebs cycle.

Thus, the correct answer is option D.