Ch. 17 Flashcards
two divisions of the ANS
sympathetic and parasympathetic
ANS is the system of
motor neurons that innervates smooth, cardiac, and glands
SNS vs ANS effectors
SNS: skeletal muscle
ANS: smooth, cardiac, and glands
ANS/SNS neurotransmitter effects
SNS: excitatory only
ANS: excitatory or inhibitory
SNS/ANS efferent pathways/ganglia
SNS: single neuron (lower motor neuron)
ANS: 2 neurons pre/post
preganglionic neuron cell body found
lateral horn
preganglionic neuron myelination
lightly
preganglionic neuron termination
autonomic ganglion
postganglionic neuron cell body is in
autonomic ganglion
post ganglion neuron myelination
unmyelinated
post ganglionic neuron termination
at effector
sympathetic E division means
flight or fight
sympathetic division symptoms
increase hr, deep breathing, dry mouth, cold sweaty skin, dilated pupils, release of glucose
resting and digesting divison
parasympathetic
parasympathetic division D
digestion, defecate, diuresis
Parasympathetic and sympathetic division innervate
same tissues, but different functions
sympathetic also referred to as
thoracolumbar divivison of ANS
parasympathetic aka
cranosacral division
Sympathetic innervates tissue
visceral organs, heart, lungs, pancreas, reproductive,
Sympathetic innervates vessels of
smooth muscle blood vessels
sympathetic preganglionic fibers length
short
sympathetic postganglionic fibers
long
since sympathetic preganglionic are short they are
closer to CNS
1 sympathetic preganglionic can synapse with
32 ganglionic neurons
sympathetic chain ganglia are found
lateral vertebral column
route of sympathetic preganglionic fibers
exit cord through ventral root
into spinal nerve
pass into white ramus communicans
enter sympathetic chain ganglion
1 option for preganglionic fibers in sympathetic chain
synapse with post ganglionic neuron in same chain ganglion
2 option for preganglionic fibers in sympathetic chain
ascend/descend sympathetic chain to synapse in diff chain ganglion
3 option for preganglionic fibers in sympathetic chain
pass through chain ganglion to synapse in collateral ganglion
postganglionic fibers for sympathetic chain ganglia enter
dorsal or ventral ramus of spinal nerves via gray ramus communicans
sympathetic postganglionic fibers exit
via sympathetic nerves
ANS collateral ganglia are located
anterior to the vertebral column
collateral ganglia are destination for fibers
inferior to T4
splanchnic nerves
nerve running sympathetic chain going out to collateral ganglia
preganglionic fibers pass through sympathetic chain and
celiac ganglion to synapse with chromaffin cells
preganglionic fibers pass through sympathetic chain and celial ganglion to synapses directly with chromaffin cells in the
adrenal medulla
chromaffin cells are modified
post ganglionic neurons
chromaffin cells release
epinephrine and norepinephrine
Parasympathetic division arrises from
cranial nerves III
VII
IX
X
parasympathetic 90% preganglionic fibers
vagus nerve
parasympathetic division preganglionic fibers synapse with
post ganglionic neurons in terminal or intramural ganglia
parasympathetic division preganglionic fibers
long
parasympatetic division post ganglionic fibers
short
parasympathetic division less divergence means
more specific response
parasympathetic division ganglia are
closer to their target (terminal)
organs parasympathetic division organs innervate
eye, salivary, glands, sweat glands
parasympathetic division does not innervate
blood vessels
most organs of the body are innervated by
both divisons of ANS