WORKSHEET 10: THE AUTONOMIC NERVOUS SYSTEM
***PREAORTIC GANGLIA are also known as PREVERTEBRAL GANGLIA*** Collectively, all
preaortic/prevertebral ganglia are what are known as COLLATERAL GANGLIA .
*** DO NOT ASSUME THAT SYMPATHETIC DIVISION CAUSES EXCITATION AND PARASYMPATHETIC
DIVISION CAUSES INHIBITION. THIS IS NOT 100% ACCURATE.***
What are the two divisions of the autonomic nervous system?
Parasympathetic: craniosacral divison
Sympathetic: thoracolumbar division
What are the two physical parts of each component of the ANS?
Neuronsganglia (preganglionic)
Ganglia target organs (postganglionic)
Which cranial nerves carry parasympathetic fibers?
CN III, VII, IX, X
Compare and contrast the sympathetic nervous system and the parasympathetic nervous system in the
following chart.
Parasympathetic Nervous System
Sympathetic Nervous System
Origin
CN III, VII, IX, X and spinal nerves
S2-S4
Spinal nerves T2-L2
Length of
preganglionic fibers
Long
Short
Neurotransmitter
released at
ganglia/effect
Ganglia location
Ach
Excitatory
Ach
Excitatory
Near or Within Target organ
Sympathetic ganglia
Collateral ganglia
Length of
postganglionic fibers
Very short
Long
Neurotransmitter
released at target
organ/effect
Ach
MOSTLY inhibitory
Ne
MOSTLY excitatory
Target organs
Glands and organs of head and
neck, thoracic, abdominal, and
pelvic organs
Arrector pilli muscle, sweat glands, skin,
blood vessels, thoracic and abdominal
and pelvic visceral organs
What are the effects of sympathetic stimulation?
Increased energy
Increased HR, BP, breathing rate
Increased muscle tone
Increased use of energy reserves (breakdown of glycogen from liver and fat from adipose tissue)
What are the effects of parasympathetic stimulation?
Increased activity in salivary glands
Increased contractions in GI tract
Stimulation of defecation and micturition
Decreased HR, BP, breathing rate
Sexual arousal
What is the main difference between the synapse of sympathetic nerves going to heart and lungs and
the ones going to abdominal organs?
The difference is the location of synapse. Sympathetic nerves going to thoracic organs and the head
and neck will go synapse at the sympathetic chain ganglia. After that synapse, postganglionic fibers
will go to head, neck, and thoracic organs.
Sympathetic nerves going to abdominal organs will bypass the sympathetic ganglia and unite to form
several splanchnic nerves that will then synapse at collateral ganglia (celiac ganglion, superior
mesenteric ganglion and inferior mesenteric ganglion).
List the GANGLIA where preganglionic fibers of the parasympathetic nervous system synapse and the
organs/structures where postganglionic fibers head to after that synapse.
CN IIIciliary ganglionintrinsic muscles of the eye
CN VIIpterygopalantine ganglion & submandibular ganglionlacrimal glands and salivary glands
CN IXotic ganglionparotid gland
CN Xintramural gangliathoracic and abdominal viscera
Spinal nerves S2-S4intramural gangliapelvic viscera
List the GANGLIA where preganglionic fibers of the sympathetic nervous system synapse and the
organs/structures where postganglionic fibers head to after that synapse.
Sympathetic chain ganglia organs of head and neck, thoracic viscera like the heart and lungs
Collateral ganglia
Celiac ganglionstomach, gallbladder, spleen, pancreas, duodenum
Superior mesenteric ganglionSmall intestine, part of large intestine
Inferior mesenteric ganglionrest of large intestine, kidneys, gonads (pelvic viscera)
***Parasympathetic fibers are not distributed in all peripheral nerves. These DON’T go to sweat glands
or blood vessels or arrector pilli muscle. Parasympathetic fibers have LIMITED distribution.