Question

In which one of the following do the two names refer to one and the same thing ?

• A. Kreb' s cycle and Calvin cycle
• B. Tricarboxylic acid cycle and citric acid cycle
• C. Citric acid cycle and Calvin cycle
• D. Tricarboxylic acid cycle and urea cycle

Answer 1

Answer: (B)

Tricarboxylic acid cycle and citric acid cycle

Answer 2

The reactions of Kreb's cycle were worked out by Sir Hans Kreb's, hence the name Krebs' cycle. It involves many 3-C compounds such as citric acid, cis-aconitic acid and iso-citric acid etc., so it is also called TCA cycle or tricarboxylic acid cycle. It involves formation of citric acid as its first product so it is called citric acid cycle. It involves production of 24 ATP molecules.