Answer:
Activation of the sympathetic branch of the autonomic nervous system results in Fight or flight response
Explanation:
The sympathetic nervous system originates in the spinal cord and its main function is to activate the physiological changes that occur during the fight-or-flight response. This component of the autonomic nervous system utilizes and activates the release of norepinephrine in the reaction. Sympathetic nervous system stimulation causes vasoconstriction of most blood vessels, including many of those in the skin, the digestive tract, and the kidneys. This occurs as a result of activation of alpha-1 adrenergic receptors by norepinephrine released by post-ganglionic sympathetic neurons.
The sympathetic nervous system activates what is often termed the fight or flight response. In response to this stimulus, postganglionic neurons principally release noradrenaline (norepinephrine). Prolonged activation can elicit the release of adrenaline from the adrenal medulla.
So in response to a stressor, the sympathetic nervous system orchestrates the fight-or-flight response. It increases muscle blood flow and tension, accelerates heart rate and respiration, and increases perspiration (sweating) and arterial blood pressure, widen bronchial passages, decrease motility of the large intestine, constrict blood vessels, increase peristalsis in the esophagus, cause pupillary dilation, piloerection (goose bumps) and raise blood pressure.
