what is ANS
system of motor neurons
what does ANS innervates
• Smooth muscle in organs and blood vessels
• Cardiac muscle
what does ANS regulate for visceral functions
• Heart rate
• Blood pressure
Somatic motor system: it is one motor neuron that extends from the __ to the skeletal muscle?
Somatic motor system: are the axons myelinated? Does it conduct impulses rapidly?
Both are yes
ANS is a chain of two motor neurons, what are they?
in ANS, Conduction is (slower/faster) than somatic nervous system
What are the divisions of the Autonomic
Sympathetic and parasympathetic
What division mobilizes the body during
extreme "fight or flight" situations
What division controls routine
Which division does "fight, flight, or fright"
When does sympathetic division gets activated
Activated during EXTREME situations
What help us respond
to dangerous situations
In what ways do sympathetic responses help us respond to dangerous situations?
-Increase heart rate and breathing rate
- Increases blood and oxygen to skeletal
- Dilates pupils and airways
- Motility of the digestive tract and urinary
tracts are inhibited
Parasympathetic division is active when?
the body is at rest
Which division is concerned w/ conserving energy?
Parasympathetic division directs what kinds of routine activities?
• Heart rate and breathing are at low normal
• Gastrointestinal tract digests food
• Pupils are constricted
Sympathetic is also called ______
Parasympathetic is also called ________
Where does Cranial outflow comes from?
What does Cranial outflow innervate?
Organs of the head, neck, thorax, and
most of abdomen
What does the Sacral outflow innervate?
Remaining abdominal and pelvic
Preganglionic fibers run via (name the nerves)
Oculomotor nerve (III)
Facial nerve (VII)
Glossopharyngeal nerve (IX)
Vagus nerve (X)
Ganglionic cell bodies located near where?
viscera/organs being innervated
Path of Vagus Nerve (CN X) sends what through parasympathetic autonomic nerve plexuses?
Sacral Outflow emerges from where?
What does Sacral Outflow innervates?
organs of the pelvis and lower abdomen
Sacral Outflow: Preganglionic cell bodies are located where?
In visceral motor region of spinal gray matter
In Sacral Outflow, axons run in where to where?
ventral roots to ventral rami
In Sacral Outflow, what do axons form?
pelvic splanchnic nerves
What do axons run through in Sacral outflow?
(or pelvic) plexus
What are splanchnic nerves?
paired nerves that contribute to the innervation of the viscera
What do splanchnic nerves carry?
fibers of ANS sensory fibers
What division are the autonomic fibers in splanchnic nerves?
What is the exception in splanchnic nerves which may carry parasympathetic?
pelvic splanchnic nerves
The Sympathetic Division issues from?
In the sympathetic division, preganglionic fibers are from where?
the lateral gray horn
Which division contains more ganglia?
Sympathetic Trunk Ganglia is located where?
both sides of the vertebral column
Sympathetic trunk ganglia is linked (short/long) nerves
Sympathetic trunk ganglia are also
Chain ganglia and Paravertebral ganglia
Sympathetic Trunk Ganglia joined to ventral rami by what?
white and gray rami communicantes
For fusion of ganglia, what is fewer than spinal nerves?
Fusion of ganglia most apparent in where?
Collateral Ganglia differ from sympathetic trunk ganglia in what three ways?
Unpaired, not segmentally arranged
Occur only in abdomen and pelvis
Lie anterior to the vertebral column
Preganglionic neurons in the thoracolumbar spinal cord send motor
axons through what first?
Adjacent ventral root into
After the preganglionic neurons in the thoracolumbar spinal cord send motor axons through adjacent ventral root, where does the motor axons go into next?
After the preganglionic neurons in the thoracolumbar spinal cord send motor axons through the spinal nerve, where does it goes next?
White ramus communicans
After the preganglionic neurons in the thoracolumbar spinal cord send motor axons into white ramus communicans, where does the motor axons go to next?
associated sympathetic trunk ganglion
In Sympathetic Pathways to the Body Periphery, what gets innervated?
Sweat glands, Arrector pili muscles, Peripheral blood vessels
Postganglionic axons travel in where?
gray rami communicantes
Gray rami contain only what?
Postganglionic fibers are what?
White rami contain what?
preganglionic fibers traveling to sympathetic trunk ganglia
Preganglionic fibers are what?
For sympathetic pathways to the head, preganglionic fibers originate in spinal
sympathetic pathways to the head: fibers ascend in the (sympathetic/parasympathetic) trunk
Postganglionic fibers associate with what?
large arteries and innervate glands, smooth muscle, and vessels throughout the head
For sympathetic pathways to thoracic organs, preganglionic fibers originate at what spinal levels?
Sympathetic fibers to heart have what?
a less direct route
Sympathetic fibers functions:
Increase heart rate
Dilate blood vessels to the heart wall
Inhibit muscles and glands in the esophagus and digestive system
For sympathetic pathways to abdominal organs, preganglionic fibers originate in spinal cord
Preganglionic fibers pass through
adjacent sympathetic trunk ganglia
After passing through adjacent sympathetic trunk ganglia, the preganglionic fibers then travel in what?
thoracic splanchnic nerves
For Pathways to the Pelvic
Organs, Preganglionic fibers originate in the spinal cord from
Pathways to the Pelvic organs: Fibers descend in where to where?
sympathetic trunk to lumbar and sacral ganglia
Inferior mesenteric ganglia or inferior
hypogastric ganglia, postganglionic fibers go from these plexuses to what?
Bladder, reproductive organs, and distal large intestine
Adrenal medulla is major organ of what system?
sympathetic nervous system
What constitutes largest sympathetic ganglia?
Adrenal medulla secretes large quantities of what to produce a widespread excitatory response, the "surge of adrenaline"
norepiniephrine and epinephrine (=adrenaline)
What is controlled by the brain stem and the spinal cord, hypothalamus and amygdala, and cerebral cortex?
Central Control of the ANS
What is the center for these e.g., cardiac center, vasomotor center and digestive activities?
Periaqueductal gray matter exerts what?
sympathetic fear response
Hypothalamus is what of the ANS?
main integration center
Amygdala is the main limbic region for what?
Raynaud's disease is characterized by what?
constriction of blood vessels
Hypertension is what?
high blood pressure
Raynaud's disease is provoked by what?
exposure to cold or by emotional stress
Hypertension can result from what?
overactive sympathetic vasoconstriction
Axons are well ___ and conduct impulses (slowly/rapidly)
in ANS, Conduction is slower than somatic nervous system due to
Thinly myelinated or unmyelinated axons
Motor neuron synapses in a ganglion