Question

During Citric Acid cycle, the various organic acid undergo decarboxylation. Which of the following organic acids of the above cycle have $4C$, $5C$ and $6C$ respectively?

• A. Pyruvic acid, Malic acid and $\alpha$-Ketoglutaric acid
• B. Pyruvic acid, $\alpha$-Ketoglutaric acid and Citric acid
• C. Oxaloacetic acid, Citric acid and Succinic acid
• D. Succinic acid, $\alpha$-Ketoglutaric acid and citric acid

Answer 1

The Correct Option is D

The Citric Acid Cycle (Krebs cycle) involves several organic acids with different carbon numbers. The key acids with 4, 5, and 6 carbons are:

Succinic acid (4C) - A 4-carbon intermediate formed after the decarboxylation of α-Ketoglutaric acid.

α-Ketoglutaric acid (5C) - A 5-carbon compound that undergoes oxidative decarboxylation to form Succinyl-CoA.

Citric acid (6C) - The 6-carbon compound formed initially by the condensation of oxaloacetate and acetyl-CoA.

Thus, the correct answer is (D) Succinic acid, α-Ketoglutaric acid and Citric acid, as these represent the 4C, 5C, and 6C acids respectively in the Citric Acid Cycle.