Activation of sympathetic nervous system increases blood pressure, increases heart rate, blood goes to skeletal muscle, blood vessel dilate, pupils dilate, and bronchioles dilate . In a controlled environment and in the absence of stress, sympathetics not needed for life . It is organized for discrete activation of localized target organ. Its main function is conservation of energy and maintenance of organ function during periods of normal activity. See decrease in heart rate, blood pressure, enhanced GI mobility and secretion, emptying of bladder, and constriction of pupils .
Energy requiring ionic pumps maintain concentration.
See delayed opening of potassium channels and repolarization process propagated down axons. These sacs go to terminal membrane where they fuse with membrane and contents get ejected. We would predict the membrane would get longer, but some membrane gets pinched off to form new synaptic vesicle. Neurons For ANS neurotransmitters, neurotransmitter synthesized in nerve terminal. These compounds are transmitted down axon to terminal .