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Question #46201
The Question
Shivering thermogenesis normally generates heat through involuntary skeletal muscle contractions. However, in a pathological state (such as Malignant Hyperthermia), a patient exhibits extreme, life-threatening heat production and rapid muscle glycogen depletion without effective sarcomere shortening. Based on the principles of muscle contraction, which of the following cellular anomalies best explains this 'metabolic burn'?
Options
- A.
Continuous leakage of Ca²⁺ from the sarcoplasmic reticulum, leading to massive ATP consumption by calcium pumps attempting to re-sequester it.
- B.
Ectopic presence of intercalated discs between skeletal muscle fibers, causing asynchronous and continuous cross-bridge cycling.
- C.
Failure of Ca²⁺ to bind to the TpC subunit of troponin, leaving myosin binding sites permanently exposed for ATP hydrolysis.
- D.
Blockage of action potential conduction deep into the muscle fiber via T-tubules, forcing a shift to heat-producing anaerobic glycolysis.
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
Shivering Thermogenesis|Calcium Cycling|ATP Hydrolysis
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Differentiating between the ATP consumed for mechanical work (myosin ATPase) versus ATP consumed for ion homeostasis (SR calcium pumps).
Students often forget that muscle relaxation (calcium reuptake into the SR) is an active, ATP-dependent process.
The trap in Option B plays on the structural differences between cardiac and skeletal muscle, while Option C tests the exact role of Troponin-C and the masking of myosin binding sites.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Animal Kingdom - Class 11 |
| Concept | Thermoregulation logic |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |