Pyruvic acid before combining with the oxaloacetic acid of Krebs cycle becomes

Options

A. cis-aconitic acid
B. acetyl Co-A
C. lactic acid
D. aceto acetic acid

Answer

To solve the question "Pyruvic acid before combining with the oxaloacetic acid of Krebs cycle becomes," we will follow these steps:

### Step-by-Step Solution:

1. **Understanding Pyruvic Acid**:
- Pyruvic acid is the end product of glycolysis, which is the metabolic pathway that converts glucose into pyruvate, releasing energy.

2. **Transition to Krebs Cycle**:
- Before pyruvic acid can enter the Krebs cycle, it must undergo a transformation. This transformation is crucial for its entry into the cycle.

3. **Conversion of Pyruvic Acid**:
- The conversion of pyruvic acid involves the removal of a carbon atom in the form of carbon dioxide (decarboxylation) and the addition of coenzyme A (CoA). This process results in the formation of acetyl-CoA.

4. **Role of Acetyl-CoA**:
- Acetyl-CoA then combines with oxaloacetic acid to form citric acid, which is the first stable compound in the Krebs cycle. This is why the Krebs cycle is also known as the citric acid cycle.

5. **Conclusion**:
- Therefore, the correct answer to the question is that pyruvic acid becomes **acetyl-CoA** before it combines with oxaloacetic acid in the Krebs cycle.

### Final Answer:
- The answer is **acetyl-CoA**.