Chapter 14 - ANS Flashcards
The preganglionic neurons’ cell bodies live ___
in the CNS
describe structure of preganglionic neurons
thin, lightly myelinated
describe structure of postganglionic neurons
nonmyelinated
postganglionic cell bodies live ___
in autonomic ganglion
effector organs of autonomic nervous system
smooth muscle, glands, cardiac muscle
What releases ACh in the autonomic nervous system?
preganglionic and postganglionic axons in the parasympathetic nervous system & preganglionic axons in the sympathetic nervous system (all except postganglionic sympathetic)
What’s the NT at the effector organs in the sympathetic nervous system?
Norepinephrine
besides ganglion, what else do some sympathetic preganglionic fibers synapse to? What do they release in that exceptional case?
adrenal medulla; release hormones norepinephrine or epinephrine into blood vessels
describe dual innervation
most of the body’s abdominopelvic and thoracic organs are innervated by both parasympathetic and sympathetic fibers
discuss the differences in the fibers’ sites of origin in the parasympathetic and sympathetic divisions
parasympathetic: fibers originate in the brain or sacral spinal nerves (craniosacral)
sympathetic: fibers originate in the thoracic and lumbar spinal cord (thoracolumbar)
discuss the differences in the relative lengths of fibers in the parasympathetic and sympathetic divisions
parasympathetic: long preganglionic and short postganglionic; sympathetic: short pre and long post
discuss the differences in the locations of ganglia in the parasympathetic and sympathetic divisions
parasympathetic: ganglia in or near visceral effector organs; sympathetic: ganglia close to spinal cord
list the ganglion & functions for the oculomotor nerve III in the parasympathetic nervous system
ciliary ganglion - constrict pupil and contract ciliary body for close vision
list the ganglia & functions for the facial nerve VII in the parasympathetic nervous system
pterygopalatine & submandibular - increase nasal secretions and tear production
list the ganglion & functions for the glossopharyngeal nerve IX in the parasympathetic nervous system
otic ganglion - increase saliva
list the plexuses of the vagus nerve X in the parasympathetic nervous system and what organs they serve
cardiac plexus - slow heart rate;
pulmonary plexus - serve lungs and bronchi;
esophageal plexus - sends branches to stomach, liver, gallbladder, pancreas, small intestine, parts of lg intestine
preganglionic fibers of the vagus nerve arise from the __ and synapse in __ ganglia in walls of target organs
medulla oblongata; intramural