Statement 1 : About `70%` of `CO_(2)` that enters `RBCs` changes into `HCO_(3)^(-)` for transport in plasma to the lungs where it reconverts into `CO_(2)` for elimination.
Statement 2 : About `40%` of `CO_(2)` that enters `RBCs` changes into carbaminohaemoglobin which releases `O_(2)` in the lungs.

Options

A. Both statement 1 and 2 correct.
B. Statement 1 is correct but statement 2 is incorrect.
C. Statement 1 is incorrect but statement 2 is correct.
D. Both statement 1 and 2 incorrect.

Explanation

To analyze the two statements regarding the transport of carbon dioxide (CO₂) in the blood, we will evaluate each statement based on the physiological processes involved.

### Step-by-Step Solution:

1. **Understanding Statement 1**:
- The statement claims that about 70% of CO₂ that enters red blood cells (RBCs) changes into bicarbonate ions (HCO₃⁻) for transport in plasma to the lungs, where it reconverts into CO₂ for elimination.
- **Analysis**:
- It is known that CO₂ is primarily transported in three forms:
- Dissolved in plasma (about 7%)
- As bicarbonate ions (HCO₃⁻) (about 70%)
- Bound to hemoglobin as carbaminohemoglobin (about 20-25%)
- The conversion of CO₂ to bicarbonate in RBCs is facilitated by the enzyme carbonic anhydrase, and this process is reversible in the lungs.
- **Conclusion**: This statement is correct.

2. **Understanding Statement 2**:
- The statement claims that about 40% of CO₂ that enters RBCs changes into carbaminohemoglobin, which releases O₂ in the lungs.
- **Analysis**:
- As mentioned earlier, the percentage of CO₂ that binds to hemoglobin to form carbaminohemoglobin is approximately 20-25%, not 40%.
- The release of O₂ from hemoglobin occurs primarily due to the Bohr effect, where increased CO₂ levels in tissues promote O₂ release, but the percentage stated is incorrect.
- **Conclusion**: This statement is incorrect.

3. **Final Evaluation**:
- Based on the analysis, Statement 1 is correct, and Statement 2 is incorrect.

### Answer:
- **Correct Option**: Statement 1 is correct, and Statement 2 is incorrect.