Partial pressure of `CO_(2)` is higher `:-`

Options

A. At alveolar level
B. At tissue level
C. In atmosphere
D. In oxygenated blood

Answer

To solve the question regarding the partial pressure of CO2 in different locations, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Partial Pressure**:
- Partial pressure refers to the pressure exerted by a single type of gas in a mixture of gases. In this case, we are focusing on carbon dioxide (CO2).

2. **Analyzing Oxygenated Blood**:
- In oxygenated blood, the partial pressure of oxygen (pO2) is high, while the partial pressure of carbon dioxide (pCO2) is low. This means that CO2 is not at a higher level in oxygenated blood.

3. **Examining Atmospheric Levels**:
- The partial pressure of CO2 in the atmosphere is approximately 0.3 mm of Hg. This value is relatively low compared to levels found in the body.

4. **Comparing Tissue Levels**:
- In tissues, the partial pressure of CO2 is around 45 mm of Hg. This is due to the metabolic processes occurring in tissues, which produce CO2 as a waste product.

5. **Considering Alveolar Levels**:
- In the alveoli of the lungs, the partial pressure of CO2 is about 40 mm of Hg. This is lower than the tissue level but higher than atmospheric levels.

6. **Conclusion**:
- Based on the above analysis, the partial pressure of CO2 is highest at the tissue level (approximately 45 mm of Hg). Therefore, the correct answer to the question is that the partial pressure of CO2 is higher at the tissue level.

### Final Answer:
The partial pressure of CO2 is higher at the tissue level.

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