Malcolm is studying alone in his room late at night when he hears a loud noise downstairs. His heartbeat increases significantly and his breathing becomes shallow. He wonders if a burglar has entered the house and decides to investigate. Which division of his nervous system was activated?
The sympathetic nervous system stimulates the fight-or-flight system which induces secretion of epinephrine and norepinephrine. This lead to an increase in heartbeat and shallow breathing.
