Tick mark of incorrect statement .

Options

A. Every 100 mL of deoxygentated blood delivers approximately 4 mL of `CO_(2)` to the alveoli.
B. Carbonic anhydrase is present in very high concentration in RBC.
C. High `p_(CO_(2)) and ` low `p_(O_(2))` in tissue help in the binding of carbon dioxide.
D. `CO_(2)` is carried in hemoglobin as carboxyhemoglobin.

Answer

To solve the question of identifying the incorrect statement regarding the respiratory system and gas exchange, we will analyze each of the provided options step by step.

### Step-by-Step Solution:

1. **Understanding the Context**:
- The question asks us to identify the incorrect statement related to the respiratory system and gas exchange. We need to evaluate each statement carefully.

2. **Analyzing the First Statement**:
- **Statement**: "Every 100 ml of deoxygenated blood delivers approximately 4 ml CO2 to the alveoli."
- **Evaluation**: This statement is correct. Deoxygenated blood does deliver about 4 ml of carbon dioxide to the alveoli for exhalation.

3. **Analyzing the Second Statement**:
- **Statement**: "Carbonic anhydrase is present in high concentration in RBC."
- **Evaluation**: This statement is also correct. Carbonic anhydrase is indeed found in high concentrations in red blood cells (RBCs) and plays a crucial role in the transport of carbon dioxide.

4. **Analyzing the Third Statement**:
- **Statement**: "High pCO2 and low pO2 in tissue help in binding of carbon dioxide."
- **Evaluation**: This statement is correct as well. In tissues, the high concentration of carbon dioxide (pCO2) and low concentration of oxygen (pO2) facilitate the binding of carbon dioxide to hemoglobin.

5. **Analyzing the Fourth Statement**:
- **Statement**: "CO2 is carried in hemoglobin as carboxyhemoglobin."
- **Evaluation**: This statement is incorrect. The correct term for carbon dioxide bound to hemoglobin is "carbaminohemoglobin." Carboxyhemoglobin refers to hemoglobin bound to carbon monoxide, which is harmful.

6. **Conclusion**:
- The incorrect statement is the fourth one, which incorrectly identifies the form in which CO2 is carried in hemoglobin.

### Final Answer:
- The incorrect statement is: **"CO2 is carried in hemoglobin as carboxyhemoglobin."**

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