The 5-C compound formed during TCA cycle is
- Fumaric acid
- α-ketoglutaric acid
- Oxalosuccinic acid
- Succinic acid
Answer
(2) α-ketoglutaric acid
Solution
In the TCA cycle: citric acid (6C) → isocitrate (6C) → [oxalosuccinic acid (6C)] → α-ketoglutaric acid (5C) + CO2.
α-ketoglutaric acid → succinyl-CoA (4C) + CO2 → succinic acid (4C) → fumaric acid (4C) → malic acid (4C) → oxaloacetic acid (4C).
∴ The 5-C compound is α-ketoglutaric acid.
Answer: (2)