Chapter 16 [ EXAM #2 ] Flashcards
is the somatic nervous system fast or slow
fast
is the autonomic nervous system fast or slow
slow
is the somatic nervous system conscious or unconscious
conscious
is the autonomic nervous system conscious or unconscious
unconscious
function: somatic nervous system
control of skeletal muscles
function: autonomic nervous system
control of visceral effectors, coordinates organ systems, maintains homeostasis
what is the HQ of the autonomic nervous system?
hypothalamus
the hypothalamus is the HQ of what nervous system?
the hypothalamus is the HQ of the autonomic nervous system
somatic efferent innervation and autonomic efferent innervation are different because of this structure…
no ganglia in somatic motor division
does somatic efferent innervation have a fast or slow impulse
the somatic motor division has a fast impulse
does autonomic efferent innervation have a fast or slow impulse
the visceral motor division has a slow impulse
does somatic efferent innervation have a large or small diameter
the somatic motor division has a large diameter
does autonomic efferent innervation have a large or small diameter
the autonomic motor division has a small diameter
are the axons in somatic efferent innervation myelinated or unmyelinated
myelinated in somatic motor division
are the axons in autonomic efferent innervation myelinated or unmyelinated
both myelinated and unmyelinated in visceral motor division
what NTs are released in the somatic motor division
acetylcholine (ACh)
what NTs are released in the autonomic efferent innervation
acetylcholine (ACh)
and norepinephrine (NE) in post-ganglion only
describe: pre-ganglionic neuron
in ANS
synapses with postganglion
location: pre-ganglionic neuron
SC or brainstem
location: post-ganglionic neroun
in PNS
function: post-ganglionic neuron
fibers extend from ganglion to visceral effectors
the hypothalamus regulates pre-/post-ganglionic neurons
pre-ganglionic neurons
diff. between neurons extending from CNS to effector in SNS and ANS
SNS: one lower motor neuron with no ganglia
ANS: two motor neurons, one pre-ganglionic body in CNS and one ganglionic body in PNS
diff. between neuron axons in SNS and ANS
SNS: thick myelinated fast
ANS: pre- thin, w/ myelin, slow
post- thinner, unmyelinated, slow
response of effectors in SNS and ANS
SNS: excitation only
ANS: excitation and inhibition
two divisions of ANS
sympathetic and parasympathetic
the sympathetic division is also referred to as…
thoracolumbar division T1 -> L2
the parasympathetic division is also referred to as…
craniosacral (cranial [3, 7, 9, 10] and sacral [S2 - S4])
quote for sympathetic division
fight or flight
quote for parasympathetic division
rest and digest
site of origin of SNS and ANS pre-ganglion neurons
lateral gray horn
location of pre-ganglionic axons in sympathetic division
ventral gray horn to the sympathetic chain ganglia
the sympathetic chain ganglia is also called…
paravertebral ganglia
function: sympathetic chain ganglia
long ganglionic neuron axons control effectors in body walls, thoracic cavity, head, limbs
function: collateral ganglia
long ganglionic neuron axons innervate tissues and organs in abdominopelvic cavity
function: adrenal gland medulla
pre-ganglionic axon goes to adrenal medulla; synapse on neuroendocrine cells → neurotransmitters (Epi, NE) released into blood (function as hormones): effects throughout body
splanchnic nerves are formed by
pre-ganglionic axons
target organs of sympathetic chain ganglia (paired)
visceral effectors: body walls, thoracic cavity, head, limbs
target organs of collateral ganglia (unpaired)
visceral effectors in abdominopelvic cavity
target organs of suprarenal medullae (paired)
organs and systems throughout body
describe sympathetic activation
[ see a bear ]
↑ alertness, feelings of energy ↓ digestive and urinary system activity ↑ heart rate and perfusion To sk. muscles, heart ↑ resp rate and bronchodilation ↑ sweat glands, ↓ salivary glands
Dilated pupils
Mobilization of energy reserves
Stimulates UMNs in cort. spinal tracts!
location and division associated with terminal ganglion
close to effector
parasympathetic
location and division associated with intramural ganglion
within organ wall
parasympathetic
describe post-ganglionic axons in parasympathetic division
short
for brief and local effects
all effect one target organ
describe pre-ganglionic axons in parasympathetic division
long
few branches
terminal and intramural
three parasympathetic cranial nerves that control structures in head
facial
oculomotor
glossopharyngeal
the nerve that supplies thoracic and abdominal organs and provides 75% of all parasympathetic overflow
vagus cn. X
function: vagus cn. X
supplies thoracic and abdominal organs and provides 75% of all parasympathetic overflow
parasympathetic sacral pre-ganglionic neurons innervate….
kidneys
urinary bladder
large intestine
rectum
reproductive organs
describe parasympathetic activation
Relaxation, food processing, and energy absorption
Constriction of pupils
↑ digestive gland secretion
↑ secretion of hormones: promote nutrient absorption
Anabolism: glycogenesis, lipogenesis
↑ specific blood flow & glandular activity: digestion, sexual arousal
↑ in digestive tract sm.muscle activity
Defecation
Contraction of urinary bladder, urination
Respiratory passageway constriction
↓ heart rate and force of contraction to low normal
general contrast of sympathetic and parasympathetic
Parasympathetic: brief, more localized impact
Relaxation, food processing, and energy absorption
Innervates specific visceral structures
Little branching of preganglionic axons
Sympathetic: Widespread, longer lasting impact
Increase alertness, energy, prepares for emergency
Preganglionic branching: reaches organs and tissues throughout body, distribution through circulation
function: cholinergic receptors
binds ACh
nicotinic
muscarinic
function: adrengic receptors
binds Epi and NE from adrenal gland
which cholinergic neurons release ACh
all pre-ganglionic neurons in ANS
all parasympathetic ganglionic neurons
some sympathetic ganglionic neurons: sweat, blood vessels, sk. muscles
function of nicotinic ACh receptors
always excitatory (ion channels open)
function of muscarinic ACh receptors
excitatory
inhibitory of cardiac muscle
epinephrine is also referred to as…
adrenaline
function of beta-2 agonist
mimics NT
function of beta-1 antagonist
opposes normal NT effect
what is dual innervation
instructions from both the sympathetic and parasympathetic divisions, one can be more dominant
one example of dual innervation is in…
autonomic plexuses
one example of parasympathetic only (independent innervation)
lacrimal glands
three examples of sympathetic only (independent innervation)
sweat glands
adrenal medulla
blood vessels
what is autonomic tone
parasympathetic and sympathetic both maintain some continual activity regulated by hypothalamus
effects activity of organ esp. in dual innervation where parasympathetic might increase and sympathetic might decrease
what are autonomic (visceral) reflexes
unconscious, automatic responses to control visceral functions
two examples of autonomic reflexes
cardiovascular reflex
micturition reflex (i.e. pee-pee)
describe sympathetic pre-ganglion axons
short
lots of branching
describe sympathetic post-ganglion axons
long
extend to target visceral organs
location of autonomic ganglia for sympathetic and parasympathetic
sympathetic = near spinal cord
parasympathetic = near effectors
