Fill in the Blanks Sympathetic ANSOnline version unit2 by Kirsten Storemski 1 physiological nicotinic internal ACH norepinephrine preganglionic sympathetic sympathetic alpha postganglionic The system of the ANS innervates most of the organs . The sympathetic arises from vertebrae T1 - L2 . The chemical neurotransmitter between the and neuron is . The receptors are . The neurotransmitter released by the postganglionic neuron on the organ is . These receptors are or beta . The action of the system is to prepare the body for fight or flight .