Which statement is wrong for Krebs' cycle?
Answer: (D) The cycle starts with condensation of acetyl group (acetyl CoA) with pyruvic acid to yield citric acid. Answer: (D) The cycle starts with condensation of acetyl group (acetyl CoA) with pyruvic acid to yield citric acid.
- A.There are three points in the cycle where NAD+ is reduced to NADH + H+
- B.There is one point in the cycle where FAD+ is reduced to FADH2
- C.During conversion of succinyl CoA to succinic acid, a molecule of GTP is synthesised
- D.The cycle starts with condensation of acetyl group (acetyl CoA) with pyruvic acid to yield citric acid✓
Correct Answer
(D) The cycle starts with condensation of acetyl group (acetyl CoA) with pyruvic acid to yield citric acid
Solution & Explanation
Answer: (D) The cycle starts with condensation of acetyl group (acetyl CoA) with pyruvic acid to yield citric acid. Solution: This statement is WRONG: the TCA cycle begins with condensation of the acetyl group with oxaloacetic acid (OAA), not pyruvic acid, to form citric acid. The other statements are correct per NCERT, three points generate NADH, one point generates FADH2, and GTP is made during the succinyl CoA to succinic acid step (substrate-level phosphorylation). NCERT: Ch 12, p.158, line ~59: "The TCA cycle starts with the condensation of acetyl group with oxaloacetic".