Question

Given below are two statements:
Statement (I): During hypoxic environment, oxygen-hemoglobin dissociation curve is shifted to the right by 2,3-BPG.
Statement (II): Carbondioxide is transported from blood to lung mostly as carbaminohemoglobin.

• A. Both Statement (I) and Statement (II) are correct.
• B. Both Statement (I) and Statement (II) are incorrect.
• C. Statement (I) is correct but Statement (II) is incorrect.
• D. Statement (I) is incorrect but Statement (II) is correct.

Hint:

A shift of the oxygen-hemoglobin curve to the right means hemoglobin holds oxygen less tightly, helping unload it to tissues. This is caused by:
- Increased 2,3-BPG
- Increased Temperature
- Increased \(CO_2\) Decreased pH (Bohr Effect)

Answer 1

The Correct Option is C

Step 1: Understanding the Concept:
This problem addresses gas transport in blood, focusing on the regulators of hemoglobin-oxygen affinity and the chemical forms in which carbon dioxide is transported from peripheral tissues to the lungs.

Step 2: Detailed Explanation:
Let us analyze both statements:

Statement (I): In a hypoxic (low oxygen) environment, such as at high altitudes, the body triggers compensatory mechanisms.
Red blood cells increase their production of the organic phosphate2,3-Bisphosphoglycerate (2,3-BPG).
2,3-BPG binds to deoxygenated hemoglobin, stabilizing its "T" (taut) state and decreasing its affinity for oxygen.
This shifts the oxygen-hemoglobin dissociation curve to theright, which facilitates the unloading of oxygen from hemoglobin to the oxygen-starved peripheral tissues. Thus, Statement (I) iscorrect.

Statement (II): Carbon dioxide is transported in the blood in three main forms:
1. Dissolved in plasma (about 7% to 10%).
2. Bound to hemoglobin as carbaminohemoglobin (about 20% to 23%).
3. As dissolvedbicarbonate ions (\(\text{HCO}_3^-\)) in the plasma (about 70%). This bicarbonate formation is catalyzed by carbonic anhydrase in red blood cells.
Since the majority of CO\(_2\) is transported as bicarbonate, not carbaminohemoglobin, Statement (II) isincorrect.
Therefore, Statement (I) is correct but Statement (II) is incorrect.

Step 3: Final Answer:
The correct option is (C).