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Question #46378
The Question
In a patient suffering from severe coronary insufficiency, the localized myocardial tissue experiences extreme hypoxia and shifts to anaerobic metabolism. Which of the following statements INCORRECTLY describes the physiological and biochemical responses in this localized ischemic region?
Options
- A.
The accumulation of lactic acid and high pCO2 causes a pronounced rightward shift of the Oxygen-Hemoglobin dissociation curve.
- B.
The localized increase in H+ concentration and pCO2 induces compensatory vasodilation of the coronary vessels.
- C.
The enhanced Bohr effect successfully restores aerobic ATP production by maximizing O2 unloading to the ischemic tissue.
- D.
Despite maximal O2 unloading favored by the Bohr effect, extreme intracellular acidosis eventually depresses the myocardial contractile machinery.
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
Bohr effect|Myocardial ischemia|Hemoglobin affinity
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Students often assume that a compensatory physiological mechanism (like the Bohr effect) is always sufficient to reverse a pathological state.
The trap lies in failing to distinguish between 'enhanced unloading kinetics' (which happens) and 'restoration of aerobic respiration' (which fails due to absolute lack of blood flow).
Additionally, it tests the NCERT concept of factors affecting the O2-Hb curve applied to a clinical scenario.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Body Fluids and Circulation - Class 11 |
| Concept | Coronary Circulation Specifics |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |