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Question #47380
The Question
During a high-intensity anaerobic sprint, the rapid contraction of white muscle fibers leads to the accumulation of a specific metabolic byproduct. According to the sliding filament theory, how does this byproduct directly induce muscle fatigue at the molecular level?
Options
- A.
By increasing the sarcoplasmic pH, which enhances the binding of ATP to the myosin head but prevents its hydrolysis.
- B.
By decreasing the sarcoplasmic pH, which inhibits myosin ATPase activity and reduces the affinity of Troponin for Ca2+ ions.
- C.
By competitively binding to the active sites on F-actin, physically blocking the attachment of the myosin cross-bridge.
- D.
By completely depleting the cellular ATP pool, preventing the detachment of the cross-bridge and causing temporary rigor.
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
Myoglobin|Mitochondria|Sarcomere_Functional_Boundaries
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Bridging the macroscopic concept of 'lactic acid accumulation' (from NCERT Locomotion chapter) with the molecular mechanics of the sliding filament theory.
Common Misconception: Students frequently assume fatigue is caused by the absolute depletion of ATP (Option D), failing to realize that metabolite-induced acidosis (H+ accumulation) acts as a feedback inhibitor to halt contractions before ATP reaches zero.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Locomotion and Movement - Class 11 |
| Concept | Red vs. White Muscle Fibers |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |