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Question #46337
The Question
In a premature neonate with severe Respiratory Distress Syndrome (due to surfactant deficiency), a systemic inflammatory cytokine storm crosses the blood-brain barrier. These cytokines specifically block the voltage-gated ion channels located at the pre-synaptic axon terminals of neurons in the medullary respiratory rhythm center. Which of the following is the most direct and immediate consequence of this inhibition on neurotransmission?
Options
- A.
Failure of Na+ influx, preventing the arrival of the action potential at the synaptic knob.
- B.
Inhibition of Ca2+ influx, preventing the movement and fusion of synaptic vesicles with the pre-synaptic membrane.
- C.
Inability of excitatory neurotransmitters to bind to ligand-gated channels, directly preventing EPSP generation.
- D.
Rapid degradation of neurotransmitters in the synaptic cleft by enzymes like acetylcholinesterase.
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
Surfactant Function|Synaptic Vesicle Exocytosis Trigger|Synaptic Delay Determinant
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Students often confuse the roles of different ions in neural transmission.
While Na+ and K+ are responsible for the generation and propagation of the action potential along the axolemma, Ca2+ is specifically required at the axon terminal for synaptic vesicle exocytosis.
The trap lies in distinguishing the direct cellular event (vesicle fusion failure) from downstream consequences (failure of EPSP generation).
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Breathing and Exchange of Gases - Class 11 |
| Concept | Surfactant Function |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |