Week 9 Flashcards
Origin of Fibers Sympathetic
thoracolumbar region of the spinal cord [T1-L2]
Origin of Fibers paraympathetic
brain stem [cranial nerves] and sacral spinal cord
Length of Fibers Sympathetics
short preganglionic and long postganglionic
Length of Fibers parasympathetics
long preganglionic and short postganglionic
Location of ganglia sympathetic
close to the spinal cord
Location of ganglia parasympathetic
in the visceral effector organs
when are the pupils constrcited?
parasymtpathetic (don’t need to see far)
which cranical nerves carry parasympathetic?
3,7,9,10
oculomotor goes to where?
eye
facial [VII] goes to where>
salivary, nasal, and lacrimal glands
glossopharyngeal [IX] goes to?
parotid salivary glands
vagus [X] goes where?
heart, lungs, and most visceral organs
where do sacral 2-4 go?
large intestine, urinary bladder, ureters, and reproductive organs
the pupils dialtes in sympathetic or parasympathetic
sympathetic
craniosacral is assocaited with what? sympathetic or parasympathetic
parasympathetic
sympathetic or parasympathetic go to skin
only sympathetic
sympathetic or parasympathetic to adrenal medulla
only sympathetic
sympathetic or parasympathetic: heart rate increases, and breathing is rapid and deep
the skin is cold and sweaty, and the pupils dilate
sympathetic
arises from spinal cord segments T1 through L2
sympathetic
sympathetic neurons produce the ____________ of
the spinal cord
lateral horns
sympathetic pregangionic nerves that do NOT synapse
sphlanic nerves
fibers from T5-L2 form _______________s and
synapse with collateral ganglia
splanchnic nerve
how many gangilai in sympathetic trunk?
23 ganglia
there are __ pathways in which the sympathetic nerve fibers reach the peripheral structure
7
where do sympathetics start?
lateral horn
these fibers innervate sweat glands and arrector pili muscles
Pathways with Synapses in Chain Ganglia
these fibers:
serve the skin and blood vessels of the head stimulate dilator muscles of the iris
inhibit nasal and salivary glands
Pathways to the Head- sympathetic
these fibers innervate the heart via the cardiac plexus, the thyroid, aorta, lungs, and esophagus
Pathways to the Thorax- sympathetic
these fibers [T5-L2] leave the sympathetic chain without synapsing
they form thoracic, lumbar, and sacral splanchnic nerves
Pathways with Synapses in Collateral Ganglia- sympathetic
- they travel through the thoracic splanchnic nerves and synapse at the celiac and superior mesenteric ganglia
- postganglionic fibers serve the stomach, intestines, liver, spleen, and kidneys
Pathways to the Abdomen- sympathetic
most travel via the lumbar and sacral splanchnic nerves to the inferior mesenteric and hypogastric ganglia
postganglionic fibers serve the distal half of the large intestine, the urinary bladder, and the reproductive organs
Pathways to the Pelvis- sympathetic
fibers of the thoracic splanchnic nerve pass directly to the adrenal medulla, upon stimulation, medullary cells secrete norepinephrine and epinephrine into the blood
Pathways to the Adrenal Medulla- sympathetic
adrenal medulla is part of what nervous system
sympathetic nervous system
no post ganglionic where?
adrenal
visceral reflexes are alwaya they are always_________ pathways
polysynaptic
pain stimuli arising from the viscera are perceived as somatic in origin
referred pain
two major neurotransmitters of the ANS
acetylcholine [ACh] and norepinephrine [NE]
preganglionics in PNS and SNS use what neurotransmitter
acetylcholine [ACh]
ACh-releasing fibers
cholinergic fibers
sympathetic postganglionic axons that release NE
adrenergic fibers
neurotransmitter effects can be excitatory or inhibitory depending upon the ____________
receptor type
the two types of receptors that bind ACh
- nicotinic
2. muscarinic
when Ach binds to a nicotinc it is
stimulatory (ALWAYS) leads to depolorization
motor end plates [somatic targets]
all preganglionic neurons of both sympathetic and parasympathetic divisions
the hormone-producing cells of the adrenal medulla
nicotinic
nicotinic these receptors blocked by the poison______ blocks NMJ causing paralysis
curare
activated nicotinic receptors stimulate the _________
somatic nervous sytem
in the CNS, release dopamine [leads to addiction]
nicotinic
can be either inhibitory or excitatory
muscarinic
the two types of adrenergic receptors
are alpha and beta
which receptors for norepinephrine are inhibiroty/ stimulatoryq
α receptors is generally stimulatory
β receptors is generally inhibitory
a notable exception:
NE binding to β receptors of the______ is stimulatory
heart (beta blockers)- reduce heart stimulation/BP
what to beta blockers do in the heart?
educeheartrate[–chronotropic]
reduceforceofcontraction[–inotropic]
what to beta blockers do in the kidneys?
reduce renin release [BP]
what to beta blockers do in the vasculatrue?
cause vasodilation [BP]
which systemp control blood pressure?
sympathetics
ANS cooperation is best seen in control of the _________________
external genitalia
___________ fibers cause ejaculation of semen in males and reflex peristalsis in females
sympathetic
____________fibers cause vasodilation and are responsible for erection of the penis and clitoris
parasympathetic
which things are ruled only by sympathetic nervous system
adrenal medulla, sweat glands, arrector pili muscles, kidneys, and most blood vessels
sympathetic impulses activate the kidneys to release_________
renin (increasing BP)
the __________ division exerts short-lived, highly localized control
parasympathetic
the__________ division exerts long-lasting, diffuse effects
sympathetic
sympathetic activation is long-lasting because of
norepinephrine
the _________ is the main integration center of ANS activity
hypothalamus
heart activity and blood pressure
body temperature, water balance, and endocrine activity
emotional stages [rage, pleasure] and biological drives [hunger, thirst, sex]
reactions to fear and the “fight-or-flight” system
hypothalamus
the effectors of the Somatic NS are ___________
skeletal muscles
the effectors of the ANS are
cardiac muscle
smooth muscle glands
axons of the ANS are a___-neuron chain
two
in the ANS:
all preganglionic fibers release _____
ACh
ANS effect on the target organ is dependent upon the neurotransmitter released and the ____________ of the effector
receptor type
sympathetic neuron preganglionic release what?
ACh
sympathetic neuron postganglionic release what?
NE
parasympathetic neuron preganglionic release what?
ACh
parasympathetic neuron postganglionic release what?
ACh
