Is the following true or false?
Parasympathetic system arises from cranial & sacral levels.  

True-the autonomic nervous system (ans) is divided into two subsystems, the parasympathetic and sympathetic systems. the systems can act to stimulate organs and tissues in opposite ways (antagonistically).example, parasympathetic stimulation acts to decrease heart rate. in contrast, sympathetic stimulation results in increased heart rate.parasympathetic fibers innervate smooth muscle, cardiac muscle, and glandular tissue. in general, stimulation via parasympathetic fibers slows activity and results in a lowering of metabolic rate and a concordant conservation of energy.with regard to specific target organs and tissues, parasympathetic stimulation acts to decrease heart rate and decrease the force of contraction. parasympathetic stimulation also reduces the conduction velocity of cardiac muscle fibers.parasympathetic stimulation of the lungs and smooth muscle surrounding the bronchi results in bronchial constriction or tightening. parasympathetic stimulation can also result in increased activity by glands that control bronchial secretions. parasympathetic stimulation of the pupil from fibers derived from the occulomotor (cranial nerve: iii), facial (vii), glossopharyngeal (ix) nerves constricts or narrows the pupil. this reflexive action is an important safeguard against bright light that could otherwise damage the retina. parasympathetic stimulation also results in increased lacrimal gland secretions (tears) that protect, moisten, and clean the eye. the vagus nerve (cranial nerve x) carries fibers to the heart, lungs, stomach, upper intestine, and ureter. fibers derived from the sacrum innervate reproductive organs, portions of the colon, bladder, and rectum.parasympathetic stimulation usually causes a dilation of arterial blood vessels, increased glycogen synthesis within the liver, a relaxation of gastrointestinal sphincters (smooth muscle valves or constrictions), and a general increase in gastrointestinal motility (the contracts of the intestines that help food move through the system.