Ch 16 Autonomic Nervous System Flashcards
(38 cards)
divisions of the nervous system
cns & pns
pns contains sensory and motor
motor contains somatic and autonomic
autonomic contains sympathetic, parasympathetic, and enteric
peripheral nerves contain what type of neurons?
sensory and motor neurons
somatic motor neurons innervate
skeletal mm
autonomic motor neurons innervate
smooth, cardiac mm, and glands
sensory neurons innervate
NOT SUBDIVIDED bc they overlap in fxn
ex: pain receptors can stimulate both somatic and autonomic reflexes
system that controls stress; fight or flight
sympathetic
system that control when not stressed; rest and digest
parasympathetic
parasympathetic and sympathetic systems work how?
both work all the time; one just always has the upper hand
the two subcategories of cholinergic receptors
muscarinic and nicotinic
_____ is always the NT for somatic motor
acetylcholine
how many neurons are in efferent pathways for somatic motor?
ONE
what receptors are in somatic motor pathways?
nicotinic cholinergic receptors
autonomic motor pathways are voluntary or involuntary?
involuntary; end up in ganglion somewhere
sympathetic division is located where?
thoracolumbar division ; which is pre ganglionic fibers from T1 to L2
most sympathetic nerves synapse where?
but some may synapse where?
in sympathetic chain ganglion (paravertebral ganglia);
collateral ganglia
the adrenal medulla acts as what?
a modified collateral ganglia producing norepinephrine and epinephrine
how many neurons are in the efferent pathway for the ANS?
2 motor neurons; preganglionic and postganglionic
what type of receptors are found in autonomic motor pathways?
cholinergic (muscarinic and nicotinic) and adrenergic (alpha and beta) receptors
preganglionic fibers synapse at different levels
divergence; ex: you get a spinal injury, but nerves can still make lungs work
postganglionic fibers receive input from different levels
convergence
all or nothing
mass activation
where does parasympathetic division stem from?
craniosacral division; which is preganglionic fibers from brainstem & S2 to S4
where does the parasympathetic division synapse?
terminal ganglia (which is close to organ)
which system uses divergence and convergence?
sympathetic system; no redundancy in parasympathetic