We just learned about the Autonomic Nervous System, which is part of the Peripheral Nervous System.
One part of the Autonomic Nervous System is the Sympathetic Nervous System.
This part of our nervous system gives us what we call the fight-or-flight feelings.
That means when something happens that scares you or hurts you, this helps make your decision for whether you run away or whether you fight back.
(from: wikipedia - sympathetic nervous system)
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