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Question #46006
The Question
A hypothetical pharmacological agent specifically blocks the Band 3 anion exchanger on the erythrocyte membrane, completely inhibiting the Hamburger phenomenon in systemic capillaries. Which of the following describes the immediate physiological cascade and its compensatory effect on respiratory volumes?
Options
- A.
Intracellular accumulation of HCO3- halts carbonic anhydrase activity, leading to systemic hypercapnia; the chemosensitive area triggers an increase in Tidal Volume (TV), thereby decreasing the available Inspiratory Reserve Volume (IRV).
- B.
Plasma accumulation of HCO3- increases blood pH, causing a leftward shift of the oxygen dissociation curve; the pneumotaxic center decreases Tidal Volume (TV) to conserve CO2.
- C.
Failure of Cl- influx causes RBC crenation, reducing O2 carrying capacity; the medulla compensates by increasing the Expiratory Reserve Volume (ERV) while keeping Tidal Volume (TV) constant.
- D.
Carbonic anhydrase activity accelerates to compensate for the blockade, causing a severe rightward shift of the oxygen dissociation curve and an acute increase in both Vital Capacity (VC) and Tidal Volume (TV).
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
Tidal Volume|Residual Volume|Carbonic Anhydrase
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Students often memorize the Chloride shift without understanding its thermodynamic purpose (preventing product inhibition of Carbonic Anhydrase).
The trap lies in linking biochemical gas exchange failure (hypercapnia) to the mechanical compensation of respiratory volumes.
Students must deduce that since Vital Capacity is a fixed anatomical parameter, any compensatory increase in Tidal Volume (TV) must mathematically exhaust the Inspiratory Reserve Volume (IRV).
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Breathing and Exchange of Gases - Class 11 |
| Concept | Respiratory Volume vs. Capacity |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |