A hiker encounters a bear, causing an immediate increase in heart rate and dilation of the pupils. Which system is activated?
Q1. A hiker encounters a bear, causing an immediate increase in heart rate and dilation of the pupils. Which system is activated?
Answer: Sympathetic nervous system
Explanation: The sympathetic system prepares the body for 'fight or flight' by dilating pupils. The parasympathetic system constricts them during rest.