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Question #46320
The Question
A researcher administers a potent, irreversible inhibitor of the enzyme carbonic anhydrase to an animal model. Despite normal arterial pO2 and haemoglobin concentration, the animal exhibits severe tissue hypoxia. Which of the following best explains the molecular mechanism behind this observation?
Options
- A.
The inhibition prevents the generation of H+ ions in erythrocytes, blunting the Bohr effect and preventing O2 unloading at the tissues.
- B.
The accumulation of CO2 in the plasma directly competes with O2 for the heme binding sites, displacing oxygen.
- C.
The lack of bicarbonate ions prevents the chloride shift, causing erythrocytes to shrink and lose their oxygen-carrying capacity.
- D.
The oxygen dissociation curve shifts sharply to the right, causing haemoglobin to release oxygen prematurely before reaching the tissues.
Check Your Answer
Correct Answer
Step-by-Step Solution
Explanation
How the Examiner Thinks
Comparative_Analysis
Sharpen your ability to evaluate multiple scenarios and distinguish between competing potential answers.
Concepts Behind This Question
Enzyme_Activation_Energy_Lowering|Haldane_Effect|Carbonic_Anhydrase
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Students often memorize that 'Carbonic Anhydrase is strictly for CO2 transport' but fail to link its byproduct (H+) to the Bohr effect and O2 unloading.
The trap lies in missing the secondary effect: without CA, oxyhaemoglobin remains locked in the high-affinity R-state, causing tissue hypoxia despite 100% O2 saturation in the blood.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Breathing and Exchange of Gases - Class 11 |
| Concept | Haldane Effect vs. Bohr Effect |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |