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Question #46340
The Question
A patient is administered a potent muscle relaxant that acts as a competitive antagonist of acetylcholine at the neuromuscular junction. Assuming no artificial ventilation is provided, which of the following best explains the immediate physiological cause of respiratory failure in this patient?
Options
- A.
Failure to establish a negative intra-pulmonary pressure gradient due to the flaccid paralysis of the diaphragm.
- B.
Cessation of action potential generation in the phrenic nerve by the medullary respiratory rhythm center.
- C.
Spastic contraction of the external intercostal muscles, fixing the thoracic cavity in an expiratory state.
- D.
Inhibition of gaseous exchange across the respiratory membrane due to sudden alveolar collapse.
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
Diaphragm|Phrenic_Nerve|Neuromuscular_Junction_Signal|Acetylcholine
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Distinguishing between central respiratory failure (neural drive suppression in the medulla) and peripheral ventilatory failure (mechanical failure at the NMJ).
Students often overlook that the diaphragm is a standard skeletal muscle and its failure to contract directly collapses the Boyle's Law logic (pressure-volume inverse relationship) required for pulmonary ventilation, even if the lungs and brain are perfectly healthy.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Breathing and Exchange of Gases - Class 11 |
| Concept | Diaphragm Mechanics |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |