lecture 10: the autonomic nervous system (ANS) Flashcards
the CNS is made up of what two “organs
brain and spinal cord
what is the function of the SC
connects the brain to the rest of the body
what are the two divisions of PNS
autonomic and somatic
what does the autonomic division do
regulates internal environment. carries info from the CNS to organs, blood, vessels, and glands
what structures does the autonomic division send signs from SNS to
organs, blood vessels and glands
what are the 2 divisions of the autonomic division
sympathetic and parasympatethic
synpathetic aorunds or inhibits the body
arouses
parasympathsetic inhibits or arouses the body
inhibts
where does the somatic division carry info
to the cns from sksetal muscels
the ANS constants of what 4 things
1) autonomic sensory neurons
2) integrating centers
3) autonomic motor neurons
4) enteric division
where are autonomic sensory neurons found
found in visceral
organs & blood vessels
(everywhere except skeletal)
where do autonomic motor neurons propagate
Propagate from CNS
to various effector tissues)
what is the enteric division
specialized network found within
walls of gastrointestinal (GI) tract).
the ANS consists of fibers that innervate voluntary or involuntary muscle
involuntary
what types of muscle fibers does ANS innervatet
smooth, cardiac and gladns
the vsiceral afferent and visceral efferent fibers travel together or seprates in the ANS
togerher
the afferent cmopoent of the ANS is comprised of
autonomic reflexs and pain fibers
what does efferent component regulate
regulation of visceral function
in the ANS there is 1 or 2 motor nervons in series
222
in the somatic system, there are 1 or 2 motor neurons in series
1
for the efferent compoent there is also 1 or two motor neruons inn seres
2 motor neurons in seeries
the 2 motor neurons in series are composed of only myelinated fibers
false
myelinated then unmyeleninated
what is the main difference betwen motor neurons in the SNS vs ANS
in the ANS there are two motor neurons in series whereas SNS is only 1 motor neuron
visceral efferent pathways of the PNS (where do the signls of the ANS travel to)
1) smooth msucles
2) cardiac msycles
3) glands
what do motor neurons in the ANS do what to smooth msucels
contract/relax
what do motor neurons in the ANS do in cardiac muscles
increae or derease rate/force of contraction
what do motor neurons in the ANS do in the glands
oncrease or decrease secretions
what is ANS orgnaized into what
nerves/ganglia and plexuses
what is a ganglia
cluster of cell bodies
what is plexuses
cluster of ganglia
true or false; ganglia/ plexuses of the ANS lie outside or inside of the spinal cord
outside
what are some examples of ANS plexuses
Celiac plexus
• Superior mesenteric plexus
• Inferior mesenteric plexus
what is anoyher nake for the sympathetic division
thoracolumbar
thoracolumbar is made from what spinal nevres
Ti-L2
what is anotyher name for the parasympathic division
craniosacral
craniosacral division is made from what nerves
4 cranial nerves (3,7,9,10)
and s2-s4
in the visceral efferent pathway of the ANS where are neurons mainly located
in lateral grey bodies with some in the anterior horn
the first visceral efferent (motor) passes throuh what
preganglionic neuron to synaptse in autonomic ganglion
the second visceral efferent (motor) passes throuh what and to where
pass through to the postganglionic neyron to the effector (smooth or cardia ms/glands)
the preganglionic neurons are callled so until they synapse with whaat
another visceral efferent neuron
where does the synapse of the preganglionic neuronn with the synapse of another vsiceral neuronn occur
in the autonomic ganglia
what are the 3 locationns of the autonomic ganglia
- Sympathetic Trunk (chain)
- Prevertebral (collateral) Ganglion
- Terminal (Intramural) Ganglion
which 2 locations of the ganglia are for the sympathetic ANS
1) Sympathetic Trunk (chain)
2. Prevertebral (collateral) Ganglion
what location of the ganglia is for parasympathic divisionn
- Terminal (Intramural) Ganglion
the sympatheic trunk (chain) is 2 long chainns where in relation to vertebra
on each side of vertebrea, parallel to it
the prevertebral ganglion is located where in relation of vert
centrally, anterior to the large abdominal arteries
true or false: the sympathtic trunk is continous or discontinuou
continous
the terminal ganglia are locaed where
very close to or in the visceral effectors (smooth muscles, cardia muscle, galnds)
in or just arounf the outside walls of organs
where do prevertebral ganglio get their names
frrom the arteries there are located in front of
what are the 2 names of prevertberal ganglionn
Celiac ganglion (celiac artery)
§ Superior & Inferior Mesenteric ganglion (superior &
inferior mesenteric artery)
both the sympathetic trunk & paravertebral ganglia recieve
their preganglionic fibers from where
the THORACOLUMBAR
SYMPATHETIC DIVISION of the ANS
the terminal ganglion receives preganglionic fibers directly from what
CRANIOSACRAL PARASYMPATHETIC division of the
ANS
all ganglia receive pre or post ganglionic neruons/fibers
preganglionic
thw The preganglionic fibers of the sym division have their cell bodies located
where
in the Lateral Grey Horns of the spinal cord
do the autonomic efferent fibers exit through the dorsal root or the ventral root
ventral root
true or false: the ANS and Somactic efferent fibers both pass through the dorsal root
false, ventral room
The Autonomic Efferent Fibers leave by what
the ventral root of the spinal nerve accompanying the Somatic
Efferent Fibers
what are the spinal segments invovled in the synpatethic divisons are
T1-T12, L1, L2
=thoracicolumbar division
how do the preganglionic fibers enter the sympathetic trunk/chain
by way of the White Rami Communicans
From the ventral ramus of the spinal nerve
the preganglionic fibers can synapse in what location
at the thoracolumbar or can go up or down to another level to synapise woth the post ganglionic neuron
after the synapse, the postganglionic fibers of the sympathtic division enters what
the ventral rami of the spinal nerve by way of the Grey Rami
Communicans
true or false: Some presynaptic (sympathetic) fibrers/neurons DO NOT
synapse in the sympathetic trunk
true
in the ANS there is 1 or 2 motor nervons in series
222
be able to describe the symapthetic divison (the way the signal travels)
.
if the presynaptic fibers of the sympathetic division do not sympase at the trunk and pass right through, they will later synapse where
in the prevertebral (collateral ganglia)
what are some examples of ganglia that are part of the prevertrbreal (collateral) ganglion
celiac
sup/inf mesentiera ganglia
what are the presynaatic nerves of the sympatheitc nervous system that synaptse in the prevertberal ganglia called
splanchnic nerves
where are splanchnin nerves found
below the diapragm
1 pressymaptic neuron may synapse with as many as how many postsynaptic nerons
20
why is is that most sympathetic responses have a wide spread effect on the body
because one presynaptic neuron can sympase with up to 20 post synaptic neurons
what is another name for celiac plexus
solar plexus
what is the celiac plexus compresed of
celiac ganglia, super mesentiec ganglian and other small ones
where does the celeiac plexus lie
in the anterior aorta at the orgion of the celiac artery
where are the preganglion cell bodies found for the parasympathetic divison
found in the lateral grey horms of the spinal cord and in the nuceli of crnail nerves 3,7,9,10
where do the preganglionic fibres/neurons in the parasympahtmic come from>
cranial nerves 3,7,9,10 and ventrial roots of spinal nerves 23-24
where do all presynaptic nerves of the parasympathetic divison synapse
in the terminal (intramural ganglion)
true or false: presynaptic neruons of the parasympathtic division pass trhough the smypathic chain
false, complettely pass through it and the prevertebral ganglion
post ganglionic fibres of the sympathetic division release what
norepinephrine
does norepinephrin increase or decrease activtiies of organs
increased
what are the fibers that release norepinephrin called
ADRENIC FIBERS
what are some aspects of fight or flight
incerase heart rate, agression ,adrenaline
increase blood flow to skeletal and cardiac (vasodilate(
vasoconstrict non essential organs
the post gangilinc fibers of the sympathetic division released noreipnephne to EVERY effector
false, all except sweat glands (they respond to actyl
all preganglionic fibers secreet what NT
acetylcholine
all postganglionic neurons secrete what NT
either acetylcholine or noreponprine (depending on sympactjeic)
postganglionic fibers of the parasympathetic division release what
acetylecholine
does acetylcholine increase or decrease the activtity of organs
decrased
fibers that release acetyl choline are called what
cholinergic gibers
what is the function of releasing acetylcholine
maintaine the organs level of actitiy to pressure
homeostatis (blanace of bodily functions)
true or false: both post and proganglionic fibers secrete acetyl cholone>
true
in stressful sitautions, what division is dominant
sympathic
in non stressful sitations, what division is dominant
parasymp
are either of the diviwions ever completely off?
no they are always on byt at varying levels
sympatanic is another nake for adregeric or cholinergic
adrenergic
parasympathtic is another name for adregernic or cholingernic
cholingernic
