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Question #47652
The Question
A tissue undergoing intense metabolism shifts to a substrate yielding a higher Respiratory Quotient (RQ), causing a localized surge in pCO2. Which of the following accurately describes the subsequent physiological cascade within the erythrocytes of the adjacent systemic capillaries?
Options
- A.
Enhanced carbonic anhydrase activity -> Increased HCO3- efflux and Cl- influx -> Elevated intracellular H+ concentration -> Decreased O2 affinity of hemoglobin (Bohr effect).
- B.
Enhanced carbonic anhydrase activity -> Increased HCO3- influx and Cl- efflux -> Decreased intracellular H+ concentration -> Increased O2 affinity of hemoglobin (Haldane effect).
- C.
Direct binding of CO2 to the heme porphyrin ring -> Formation of carbaminohemoglobin -> Cl- influx into erythrocytes -> Rightward shift of the oxygen dissociation curve.
- D.
Enhanced carbonic anhydrase activity -> Increased HCO3- efflux and Cl- influx -> Decreased intracellular H+ concentration -> Leftward shift of the oxygen dissociation curve.
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
Respiratory Quotient (RQ) Constants|Chloride Shift (Hamburger Phenomenon)|Partial Pressure Gradient Logic
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Integrating the Hamburger phenomenon with the Bohr effect while avoiding anatomical and biochemical location traps.
Students frequently confuse the direction of the Chloride shift at the systemic vs. alveolar capillaries, and mistakenly believe CO2 binds to the heme group rather than the globin chain.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Respiration in Plants - Class 11 |
| Concept | Respiratory Quotient (RQ) Constants |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |