Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
53 Cards in this Set
- Front
- Back
Somatic efferent
|
Produces voluntary skeletal muscle contractions
|
|
Autonomic (visceral efferent)
|
System consists of:
gen. visceral sensory (afferent)neurons gen. visceral motor (efferent) neurons visual effectors involuntarily regulates visceral activities Sympathetic nervous system Parasympathetic nervous system efferent fibers: preganglionic and postganglionic many visceral organs have dual innervation - not all |
|
Visceral effectors
|
smooth and cardiac muscle
glands |
|
Autonomic nervous system
|
Sympathetic nervous system
Parasympathetic nervous system |
|
Sympathetic nervous system
|
prepares the body for stress
|
|
Parasympathetic nervous system
|
producing a "rest relaxation" response
|
|
Visceral efferent fibers
|
Preganglionic fibers
Postganglionic fibers |
|
Preganglionic fibers
|
Run from the c.n.s. to autonomic ganglia
|
|
Postganglionic fibers
|
Run from autonomic ganglia to visceral effectors
|
|
"autonomic ganglia"
|
A ganglion occurs btwn. preganglionic and postganglionic fibers
|
|
Sympathetic nervous system
|
Preganglionic neurons (thoracolumbar outflow)
Autonomic ganglia Sympathetic trunk ganglia Prevertebral ganglia Autonomic plexuses Postganglionic neurons White rami communicants Gray rami communicants |
|
Why is the sympathetic response (stress reaction) so widespread in the body?
|
"1" preganglionic fiber can stimulate up to "20" plus postganglionic neurons that supply different organs - thus stress reaction widespread
neurotransmitters get into blood and remain a while before being broken down. |
|
Visceral efferent pathways
|
consists of two neurons:
Preganglionic neurons Postganglionic neurons |
|
Preganglionic neurons
|
run from C.N.S. to ganglion
Most are myelinated (white) fibers |
|
Postganglionic neurons
|
run from ganglion to visceral effectors
Are unmyelinated (gray) fibers |
|
Preganglionic neurons
|
thoracolumbar division
Cell bodies originate in lateral gray horns of T1 - T2 Axons terminate in autonomic ganglia of the s.n.s. |
|
Prevertebral ganglia (collateral)
EXAMPLES |
Celiac
Sup. mesenteric ganglion Inf. mesenteric ganglion |
|
Splanchnic nerves
|
Are preganglionic neurons
belong to s.n.s. bypass or pass through sympathetic trunk and terminate in collateral ganglia |
|
Autonomic plexuses
|
In thorax
abdomen and pelvic region of body are network of axons of both sympathetic and parasympathetic neurons |
|
Preganglionic neurons (craniosacral outflow)
|
Cell bodies of parasympathetic in nuclei of cranial nerves III, VII, IX, and X and lateral gray horns of S2 - S4 (sacral parasympathetic outflow)
Axons terminate in autonomic ganglia of the P.N.S. |
|
Postganglionic neurons
|
Cell bodies from autonomic ganglia (sym. trunk and collateral ganglia - terminate in visceral effectors)
|
|
White rami communicants
|
Branches - connect ventral root of sp. nerve with sympathetic trunk
are myelinated preganglionic fibers |
|
Gray rami communicants
|
Run from ganglia back to ventral ramus of sp. nerve
are gray postganglionic neurons |
|
Autonomic ganglia of P.N.S.
|
Terminal ganglia (intramural)
May be divided into 3 gen. groups sympathetic division parasympathetic division |
|
Terminal (intramural) ganglia
|
Preganglionic axons of the parasympathetic division synapse with postganglionic neurons
located close to or actually within the wall of a visceral organ. longer the most axons of sympathetic preganglionic EXAMPLES neurons ciliary pterygopalatine submandibular otic |
|
Postganglionic neurons
|
The 2nd autonomic neuron in an autonomic pathway having its cell body an dendrites located in an autonomic ganglion and it's a myelinated axon ending at cardiac muscle, smooth muscle, or a gland.
|
|
Neurotransmitters
|
Ap. 50 + known
one neuron may contain several types Released at: endbulbs Synapse Neuroeffector junction Cholinergic fibers Adrenergic fibers |
|
synapse
|
space btwn. axonal ending and dendrite or effector
|
|
Neuroeffector junctions
|
Specifically btwn. postganglionic axonal ending and effector
|
|
Cholinergic fibers
|
release acetylcholine (Ach)
is released at: Sympathetic and parasympathetic preganglionic axons All parasympathetic postganglionic axons Few sympathetic postganglionic axons Ach inactivated by acetycholinesterase (AchE) |
|
Acetylcholine
|
esp. excites - as in the contraction of skeletal muscle - but - it can also inhibit cardiac muscle - thus receptors determine effect of neurotransmitters
|
|
Adrenergic fibers
|
released norepinephrine
released at most sympathetic postganglionic axons |
|
norepinephrine
|
inactivated slowly by:
Catechol-o-methyltransferase (COMT) Monoamine oxidase (MAO) may enter the bloodstream secreted from adrenal medulla |
|
Sympathetic reaction
|
prepares body for stress - "fight or flight" response
|
|
Parasympathetic reaction
|
restores and/or conserves energy - "rest and repair" response
|
|
Sweat glands
(visceral effector) |
s.n.s stimulation: secretion gen. up
p.n.s stimulation: no known innervation |
|
Gastric secretion
(visceral effector) |
s.n.s stimulation: secretion inhibited
p.n.s stimulation: increased secretion |
|
Muscles of bronchi
(visceral effector) |
s.n.s stimulation: relation leads airway dialation
p.n.s stimulation: contraction leads to airway contriction |
|
Heart rate
Force of contraction (visceral effector) |
s.n.s stimulation: Increased heart rate and force of atrial and ventrile contractions
p.n.s stimulation: Decrease heart rate and Decreased force of atrial contraction |
|
Blood vessels to:
Skin (periphery) Skeletal muscles (visceral effector) |
s.n.s stimulation: Contraction leads to vasocontriction; relaxation leads to vasodialation
p.n.s stimulation: Vasodialation, which may not be physilogically significant S.M. No known effect |
|
Intestines
(visceral effector) |
s.n.s stimulation: decreases
motility and tone; contraction of sphincters p.n.s stimulation: Increased motility and tone; relaxation of sphincters |
|
Visceral autonomic reflexes
|
Consists of:
Receptor Afferent(sensory) neuron Association neuron Visceral efferent preganglionic neuron Visceral efferent postganglionic neuron Visceral effector |
|
Visceral autonomic reflexes
|
responses that occur when nerve impulses pass over an autonomic reflex arc
regulating controlled condition of body - blood pressure - digestion |
|
Receptor
|
distal end of sensory neuron
responds to a stimulus and produces a change that will ultimately trigger nerve impulses. |
|
Sensory (afferent) neurons
|
Conducts nerve impulses from receptors to the CNS.
|
|
Association neuron
|
A nerve cell found entirely within the central nervous system that acts as a link between sensory neurons and motor neurons.
|
|
Visceral efferent
|
smooth muscle
cardiac muscle glands |
|
Hypothalamus
|
receives input from or is linked to:
Higher brain centers Emotions Visceral functions senses others |
|
SNS
|
appears to be controlled by post. and lat. portions of the hypothalamus.
|
|
PNS
|
appears to be controlled by ant. and med. portions of the hypothalamus.
|
|
Meditation
|
mind and body
trance like state clearing your mind for relaxation |
|
Biofeedback
|
A technique in which an individual is provided w/ info regarding an autonomic response such as heart rate, blood pressure, or skin temp. using electronic devices
|
|
Progressive relaxation
|
tense and relax different parts of body and then learning how to relax those muscles.
|