Which part of the human autonomic nervous system triggers the 'fight-or-flight' stress response by elevating heart rate, dilating bronchioles, and inhibiting digestion?
Answer and explanation
Correct answer: A. Sympathetic nervous system
- Step 1: Differentiate functional subdivisions of the autonomic nervous system.
- Step 2: The sympathetic nervous system coordinates stress responses via noradrenaline and adrenaline release, promoting increased cardiac output, airway dilation, and pupil dilation while shunting blood away from the digestive tract.
Answer
Sympathetic nervous system.
Why not the others: Parasympathetic division governs 'rest and digest' activities; enteric governs gut motility locally; somatic system controls voluntary skeletal muscles.
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