Honors Anatomy amp Physiology ANS in PNS operates via reflex arcs includes autonomic sensory neurons integrating centers in CNS autonomic motor neurons Autonomic reflex arc Autonomic Motor Neurons ID: 774774
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Slide1
The Autonomic nervous system
Honors Anatomy & Physiology
Slide2ANS
in PNS
operates via reflex arcs
includes:
autonomic sensory neurons
integrating centers in CNS
autonomic motor neurons
Slide3Autonomic reflex arc
Slide4Autonomic Motor Neurons
when somatic motor neurons sends impulse to a muscle the effect always excitatory…if they stop sending impulses that muscle atrophies
autonomic motor neurons regulate visceral activities by either increasing (exciting) or decreasing (inhibiting) ongoing activities in their
effector
tissues (cardiac or smooth muscle, glands)
Slide5Comparisons of aNS & Somatic NS
Slide6Autonomic sensory neurons
source of most input to ANS via sensory receptors called
interoceptors
not consciously perceived most of time
located in:
blood vessels
v
isceral organs
muscles
in nervous system
Slide7Autonomic responses
most cannot be altered to any great degree making some responses ideally suited for lie detector tests
Slide8Autonomic Motor Pathways
most consist of 3 motor neurons in series
1
st
neuron has cell body in CNS
myelinated
axon synapses in autonomic
ganglion
with 2
nd
motor neuron cell body: its
unmyelinated
axon
effector
except
Slide9Autonomic Motor Pathway
Slide102 Branches of Motor part of ANS
Sympathetic Division
Parasympathetic Division
preganglionic axons from thoracolumbar nervesganglia far from visceral effector in:sympathetic chain or collateral ganglianeurotransmitter used:ACh in gangliaNE in effector organ
preganglionic
axons from
craniosacral
nerves
ganglia
near
or w/in visceral
effector
organs
neurotransmitter used:
ACh
in ganglia
ACh
in
effector
organ
Slide11Motor part of ANS
most organs have dual
innervation
nerve impulses from 1 will increase activity (excitation) & impulses from other decrease activity (inhibition)
Slide12Slide13Sympathetic ganglia
2 groups:
sympathetic trunk ganglia
lie in vertical row, either side of vertebrae
p
revertebral
ganglia
lie anterior to vertebral column close to large abdominal arteries
Slide14Sympathetic division of ANS
Slide15Parasympathetic ganglia
most close to or w/in effector organ
Slide16Slide17Effects of sympathetic & parasympathetic divisions of the ans
Slide18Homeostatic Imbalances of the ans
Raynaud’s phenomenon:due to excessive sympathetic stimulation of smooth muscles in arterioles of digitsdigits become ischemic (lack of blood) after exposure to cold or with emotional stress
Slide19Medical terminology
autonomic nerve neuropathy:
often caused by long-standing diabetes, neuropathy affects 1 or more autonomic nerves, can interfere with reflexes
hyperhydrosis
:
profuse sweating due to intense stimulation of sweat glands
vagotomy
:
cutting
vagus
nerve; often done to decrease production of
HCl
in patients with severe ulcers
Slide20