sympathetic and parasympathetic nervous system

adrenal adrenaline airways anatomical anatomy autonomic biology bladder body brain care cell central cerebellum cerebral cervical connection cord design diagram difference digestive education eye gallbladder guide health heart human icon illustration infographic inhibit inner internal intestine kidney lumbar lung medical medicine nerve nervous network neural neurology noradrenaline organ parasympathetic psns pupil rate saliva science scientific secrete sensory signal sns spinal spine structure sympathetic system thoracic vector