Chapter 8 Flashcards
ANS
two motor neuron system- in the periphery
focusing on paths and fibers on the peripheral nervous system
unlike somatic efferent that has one
ANS
involuntary unconcious control
for motor control of most internal organs, smooth muscle of gut and blood vessels, skin glands, cardiac muscle, regulate heart rate
ANS divides into
sympathetic (immediate) – Fight or flight, fear
parasympathetic(long term)-rest, rumination (digestion), calm
BOTH are involuntary, and for survival
sympathetic
- Neurotransmitter: norepinephrine
- Turn OFF most gut activities. (digestive)
- Dilate blood vessels to musculo-skeletal structures to defend yourself
- Constrict blood vessels to internal organs reduce blood flow
- *two motor neuron,Synapses away from target structure.
parasympathic
- Neurotransmitter: acetylcholine
- Turn ON most gut activities.
- Constrict blood vessels to musculo-skeletal structures and brain. gut needs it not skeletal
- drooling
- Dilate blood vessels to internal organs.
- two motor neuron,Synapses on or near target structure.
autonomic fiber placement:
sympathetic:
parasympathetic:
symp: thoracolumbad carrying pregangloic(t1,L2)
para:cranio-sacral carries pregangloic (Cnn 3, 7, 9, 10; S2-4 )
para “parllel to sympathetics” parasympathetic
what terms do we use for the ANS when talking about synapses?
Pregangloic(are emerging), and post gangloinic because the synapse occurs in a ganglion
(synapse in other terms occurs on or near the cell body)
parasympathetic
the ganglia, where the synapse occurs when it is on or near the target strucuture, this means that the first neuron (pregangloic one) is a long fiber, has a long axon because it has to go all the way to the target structure before it synapses, very short postgangloic fiber
parasympathetic ganglia?
Ganglia are not easily dissectable, embedded in wall of structure, longer ganglia, bigger and vissible with the eye (parasymp) deep inside
very particular parasymp. ganglia,
head:Ciliary, Pterygopalatine, Otic, Submandibular , all targets are in head near structure
Intramural(within the walls, inside of target sturcures, synapes on the target strucure) Ganglia,
sympathetic innervation
Synapses away from the target structure at paravertebral (collateral)->preaortic ganglia
-ganglia easily dissectable
how are pregang fibers and long gang fibers like in the sympathetic
pre-short
post-long
opposite of parasympathetic pre-long post-short
paravertebral ganglia (sympathetic innervation)
Superior Cervical, Middle Cervical, Inferior Cervical, Cervicothoracic
-form the sympathetic trunk
(goes up and down adjacent to verterbral column)
preaortic ganiglia (sympathetic innervatio)
Celiac, Superior & Inferior Mesenteric Ganglia
Preaortic (Prevertebral or Collateral)
ventral to the aorta is paravertebral or preaortic ganglia?
preaortic(collateral), along surface of the aorta, nerves are going to collect right next to the aorta, on the anterior portion of the aortia
the chain of ganglia in symp. inntervation is made out of what and forms what?
made out of paravertbral ganglia all together connected= forms symp. trunk
the symp trunk stretches?
extend all way up to neck and up to base of brain
paravertbrals
in the neck does not recieve fibers, no symp. emerge from the cervical region, only taking what is recieves from thoraic lumbar carries in the neck
specific paravertebral location
in your neck, you’re going to have your Superior Cervical ganglion, Middle Cervicalganglion, Inferior Cervicalganglion
-at junction before you go from your throaic into your neck=Cervicothoracic ganglion
synapse of paravertbral
preganglics can enter into the sympathetic trunk they can synapse inside the ganglia of the symp. trunk and then they can go out to the target strucutre, goes out into ventral or dorsal ramus can go to hyp. expaxial skin structures
can go out and synapse into inside symp. trunk will go to target structures in head (eyes)
or can go directly to thoaric organ to heart and lungs
or preaortic ganglia, (mesenterys)complete bypass the symp. trunk, will go past without synapsing will go to one of those ganglia, reach because of specific nerves
we’re going to use the greater splanic nerve(only carries pregangloic fibers) to the celiac ganglion
-lesser splanic pregangloic sympathetcis fibers to superior mesentery ganglion
-lumbar splanic nerves, inferior mesentery ganglion
once they synapse there they can go to their target structures then you have short pre gangloic and long post ganglioc fibers going to your viscera
what is a plexus?
A complex interconnection of adjacent nerves.
explain the sympathetic ganglion chain
innervates visceral effoctors via spinal nerves, innervates visceral organs in thoracic cavity via symp. nerves
each ganglia connects to each other =symp. nerve trunk
4 options
explain the collateral ganglion chain
innervates visceral organs abdominopelvic cavity
explain in detail what a auto. plexus is
- Adjacent autonomic nerves are sorted and recombined so that fibers of a particular terminal nerve contain elements from both sympathetic and parasympathetic innervation c
- instead of combing somatic from c4,c5,c6 and going into the plexsus you’re combing autonomic interveration,visceral efferent from sympatheitc and parssympathic which are coming from totally different locations (craniosacral, and thoraclumbar) in a plexsus so they can be reorganized and go into a target structure
ex. stomach, bladder needs para and symp.
embryology
embryo starts to fold in ventral direction, opening to the yolk sac begins to slowly close off
embryology
connection to yolk sac, midgut-before that foregut, behind hindgut
embryonic structure foregut
1vasculature:
2symp innervation:
3para. innervation:
1celiac trunk
2greater splanchnic nerve
3 vagus nerve
embryonic structure midgut
1vasculature:
2symp innervation:
3para. innervation:
1 cranial mesenteric artery
2lesser spanchnic nerve
3 vagus nerve
embryonic structure hindgut
1vasculature:
2symp innervation:
3para. innervation:
1caudal, inferior mesenteric artery
2least splanchnic nerve
3pelvic splanchnic nerve(s2-s4)
