Assertion : At the tissue level, 70 percent of `CO_(2)` formed from contabolism is trapped as bicarbonate in the RBCs.
Reason : At tissue level, carbonic anhydrase in RBCs facilites the formation of `CO_(2)` and `H_(2)O` from bicarbonate.

Options

A. If both assertion and reason are true and reason is the correct explanation of assertion
B. If both assertion and reason are true and reason is not the correct explanation of assertion
C. If assertion is true but reason is false.
D. If both assertion and reason are false.

Explanation

To solve the assertion and reason question, we will analyze both statements step by step.

### Step 1: Analyze the Assertion
The assertion states that "At the tissue level, 70 percent of CO₂ formed from catabolism is trapped as bicarbonate in the RBCs."

- **Explanation**: When cells metabolize nutrients, they produce carbon dioxide (CO₂) as a waste product. A significant portion of this CO₂ is converted into bicarbonate ions (HCO₃⁻) in red blood cells (RBCs) for transport to the lungs.

### Step 2: Analyze the Reason
The reason states that "At the tissue level, carbonic anhydrase in RBCs facilitates the formation of CO₂ and H₂O from bicarbonate."

- **Explanation**: Carbonic anhydrase is an enzyme present in RBCs that catalyzes the reaction between CO₂ and water (H₂O) to form carbonic acid (H₂CO₃), which then dissociates into bicarbonate (HCO₃⁻) and hydrogen ions (H⁺). This process is crucial for the conversion of CO₂ into bicarbonate for transport.

### Step 3: Evaluate the Truth of Each Statement
- The assertion is **true** because it correctly states that 70% of CO₂ is indeed converted to bicarbonate in RBCs.
- The reason is also **true** because it accurately describes the role of carbonic anhydrase in facilitating the conversion of CO₂ and H₂O into bicarbonate.

### Step 4: Determine the Relationship Between Assertion and Reason
- The reason provides a correct explanation for the assertion, as it describes the biochemical process that allows for the trapping of CO₂ as bicarbonate in RBCs.

### Conclusion
Both the assertion and reason are true, and the reason correctly explains the assertion. Therefore, the correct answer is that both the assertion and reason are true, and the reason is the correct explanation of the assertion.

### Final Answer
**Both assertion and reason are true, and the reason is the correct explanation of the assertion.**

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