Respuesta :
I believe that would be the Sympathetic and Autonomic nervous system, because that sounds like the fight or flight response.
A branch falls suddenly, almost hitting him, and his heart suddenly starts racing so the sympathetic nervous system releases the hormones called (catecholamines - norepinephrine and epinephrine ) to race the heart rate.
What is sympathetic nervous system?
The sympathetic nervous system refers to system that connects the internal organs to the brain by spinal nerves. When stimulated, these nerves stimulate the organism for stress by increasing the heart rate, increasing blood flow to the muscles, and decreasing blood flow to the skin.
Norepinephrine is a neurotransmitter used by part of the nervous system activated during stress known as the sympathetic nervous system.
For more information regarding sympathetic nervous system, visit:
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