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Question #46308
The Question
A person relocates to a high-altitude region and experiences chronic hypoxia. After a few weeks, their erythrocytes exhibit elevated levels of 2,3-bisphosphoglycerate (2,3-BPG). Which of the following best describes the physiological consequence of this adaptation on the oxygen-hemoglobin dissociation curve and its functional significance?
Options
- A.
A rightward shift of the curve, which decreases hemoglobin's affinity for O2, ensuring enhanced oxygen unloading at the peripheral tissues.
- B.
A leftward shift of the curve, which increases hemoglobin's affinity for O2, ensuring maximum oxygen saturation in the pulmonary capillaries.
- C.
A rightward shift of the curve, which primarily decreases the total oxygen-carrying capacity of erythrocytes to compensate for low atmospheric pO2.
- D.
A leftward shift of the curve, driven by an allosteric change in hemoglobin, which prevents premature oxygen dissociation in the systemic arteries.
Check Your Answer
Correct Answer
Step-by-Step Solution
Explanation
How the Examiner Thinks
Regulatory_Failure
Understand how NOT, EXCEPT, and logical constraints are used to manipulate exam results.
Concepts Behind This Question
HbO2|2,3-BPG|Erythrocyte_Metabolism
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Students often intuitively assume that under low oxygen conditions (hypoxia), the body must adapt by binding oxygen more tightly (a left shift).
The trap exploits the failure to distinguish between 'decreased affinity' (which beneficially enhances tissue unloading) and 'decreased capacity'.
The physiological priority during hypoxia is oxygen delivery to tissues, which requires a right shift.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Breathing and Exchange of Gases - Class 11 |
| Concept | Oxygen-Hemoglobin Dissociation Curve |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |