Which of the following is high energy molecule produced by oxidative decarboxylation in aerobic respiration but is neither the intermediate of TCA nor EMP ?

Options

A. `NADH+H^(+)`
B. ATP
C. Acetyl CoA
D. Succinyl CoA

Answer

To solve the question, "Which of the following is a high energy molecule produced by oxidative decarboxylation in aerobic respiration but is neither the intermediate of TCA nor EMP?", we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Terms**:
- **Oxidative Decarboxylation**: This is a biochemical process where a carboxyl group is removed from a molecule as carbon dioxide (CO2) and the molecule is oxidized, leading to the production of energy-rich compounds.
- **TCA Cycle (Krebs Cycle)**: A series of chemical reactions used by all aerobic organisms to generate energy through the oxidation of acetyl-CoA derived from carbohydrates, fats, and proteins.
- **EMP Pathway (Glycolysis)**: The Embden-Meyerhof-Parnas pathway is the process of converting glucose into pyruvate, producing ATP and NADH in the process.

2. **Identify the Process**:
- In aerobic respiration, glucose is first converted to pyruvate through glycolysis (EMP pathway).
- Pyruvate then undergoes oxidative decarboxylation to form acetyl-CoA. This is where the oxidative decarboxylation occurs.

3. **Recognize the High Energy Molecule**:
- During the conversion of pyruvate to acetyl-CoA, energy is released, and acetyl-CoA is considered a high-energy molecule.

4. **Determine the Relationship with TCA and EMP**:
- Acetyl-CoA is not an intermediate of the TCA cycle itself; it enters the cycle but is not produced during it.
- It is also not part of the EMP pathway, as the EMP pathway ends with the formation of pyruvate.

5. **Evaluate the Options**:
- **NADH plus hydronium ion**: This is produced during glycolysis and is part of the TCA cycle.
- **ATP**: This is produced during glycolysis and the TCA cycle, but not specifically from oxidative decarboxylation.
- **Acetyl-CoA**: This is produced from pyruvate through oxidative decarboxylation and is a high-energy molecule.
- **Succinyl-CoA**: This is an intermediate in the TCA cycle.

6. **Conclusion**:
- The correct answer is **Acetyl-CoA**, as it is the high-energy molecule produced by oxidative decarboxylation in aerobic respiration and is neither an intermediate of the TCA cycle nor the EMP pathway.

### Final Answer:
**Acetyl-CoA**