In cell respiration, which does not involove EMP pathway?

Options

A. Pyruvic acid into `CO_2 and H_2O`
B. Glucose into lactic acid
C. Glucose into `CO_2 and H_2O`
D. Glucose into alcohol

Answer

To determine which process in cellular respiration does not involve the Embden-Meyerhof-Parnas (EMP) pathway, we need to analyze each option provided in the question. The EMP pathway is another name for glycolysis, which is the process that converts glucose into pyruvate.

### Step-by-Step Solution:

1. **Understand the EMP Pathway**: The EMP pathway, or glycolysis, is the first step in cellular respiration where glucose is broken down into pyruvate, producing ATP and NADH in the process.

2. **Analyze Each Option**:
- **Option A: Pyruvic acid into carbon dioxide and water**:
- Pyruvic acid is the end product of glycolysis (the EMP pathway). This process typically occurs in the Krebs cycle (or citric acid cycle) where pyruvate is further oxidized to produce carbon dioxide and water. Since this step does not involve the EMP pathway, it is a candidate for the correct answer.

- **Option B: Glucose into lactic acid**:
- This process is known as lactic acid fermentation. It begins with glycolysis, where glucose is converted to pyruvate, which is then reduced to lactic acid. This option involves the EMP pathway.

- **Option C: Glucose into carbon dioxide and water**:
- This represents the complete oxidation of glucose, which includes glycolysis followed by the Krebs cycle and oxidative phosphorylation. Therefore, this option also involves the EMP pathway.

- **Option D: Glucose into alcohol**:
- This is alcoholic fermentation, which also starts with glycolysis where glucose is converted to pyruvate, and then pyruvate is converted into alcohol (ethanol). Thus, this option also involves the EMP pathway.

3. **Conclusion**:
- The only option that does not involve the EMP pathway is **Option A: Pyruvic acid into carbon dioxide and water**. This process occurs after glycolysis and is part of the Krebs cycle.

### Final Answer:
**Option A: Pyruvic acid into carbon dioxide and water does not involve the EMP pathway.**