Which physiological response is most consistent with activation of the parasympathetic nervous system?

• A. Pupil dilation and decreased salivation
• B. Increased sweating and increased blood glucose via glycogenolysis
• C. Decreased heart rate and increased gastrointestinal motility
• D. Increased heart rate and bronchodilation

Answer: (C)

Verified step by step guidance

1. Understand the role of the parasympathetic nervous system (PNS), which is primarily responsible for 'rest and digest' activities, promoting bodily functions that conserve energy and support digestion.
2. Recall that activation of the PNS typically results in decreased heart rate, increased digestive activity (such as increased gastrointestinal motility), constriction of pupils, and increased salivation.
3. Analyze each option by comparing it to the known effects of the PNS: Pupil dilation and decreased salivation are sympathetic responses, not parasympathetic.
4. Increased sweating and increased blood glucose via glycogenolysis are also sympathetic responses related to 'fight or flight' mechanisms.
5. Therefore, the option describing decreased heart rate and increased gastrointestinal motility aligns with the parasympathetic nervous system's physiological effects.