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Question #47400
The Question
During a severe metabolic crisis resulting in complete intracellular ATP depletion within the skeletal muscles of the appendicular system, the limbs become locked in a state of extreme rigidity (similar to rigor mortis). According to the sliding filament theory, this systemic locking occurs specifically because:
Options
- A.
Hydrolysis of ATP into ADP and Pi fails to occur, preventing the formation of the cross-bridge.
- B.
The absence of a new ATP molecule prevents the detachment of the myosin head from the F-actin filament.
- C.
Calcium ions are unable to bind to the troponin complex, keeping the active sites on actin permanently unmasked.
- D.
The release of ADP and Pi from the myosin head is inhibited, preventing the execution of the power stroke.
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
Appendicular Girdle|Cross-bridge Cycling Energy|Actin-Myosin
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Students often mistakenly believe that ATP is solely required to provide energy for the contraction (power stroke).
The critical NCERT nuance is that the mere binding of a new ATP molecule (prior to its hydrolysis) is the absolute prerequisite for breaking the cross-bridge and allowing muscle relaxation.
Failing to distinguish between ATP hydrolysis (cocking the head) and ATP binding (detaching the head) is the primary trap.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Locomotion and Movement - Class 11 |
| Concept | Appendicular Girdle Mechanics |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |