Monica sees a snake nearby, senses danger, and immediately sprints in the opposite direction. What MOST likely caused this “fight or flight” response?

The sympathetic nervous system triggers the body’s rapid “fight or flight” response when it senses danger. It prepares Monica to act quickly, such as by sprinting away from the snake. The parasympathetic nervous system instead supports rest and recovery; leukocytes and lymphocytes are types of immune cells.

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