NTA Abhyas NEET2020BotanyRespiration in PlantsPractice
Substrate level phosphorylation occurs during which step of Krebs' cycle?
Options
- ASuccinyl- C o A → Succinic acid
- BIsocitric acid → Oxalosuccinic acid
- COxalosuccinic acid → ketoglutaric acid
- DMalic acid → O A A
Correct answer
A. Succinyl- C o A → Succinic acid
Step-by-step solution
Succinyl co-A (4C) undergoes hydration (addition of water) to form Succinic acid (4C) in the presence of enzyme Succinyl thiokinase. The energy liberated in this reaction is used to combine GDP & iP to form GTP (Guanosine triphosphate). GTP is relatively unstable and is soon transformed to ATP using ADP. Thus ATP is generated by substrate level phosphorylation (without ETS)