Download Peripheral Nervous System Structures

Peripheral Nervous System Structures
Purpose:
 To identify cranial nerves and their targets
 To identify selected nerves of the cervical, brachial, lumbar, and
sacral plexus.
 To identify the target muscles (or other organs) of the selected
nerves
 To identify selected autonomic nerves and ganglia.
Each student will locate the following nerves and ganglia of the peripheral
nervous system (PNS). Nerves are bundles of many axons supported by
several layers of connective tissue (analogous to the arrangement of muscle
fascicles in muscles) and will appear as long tough fibrous strands. Each axon in
a nerve may be either sensory, carrying information to the CNS (brain and spinal
cord), or motor, carrying commands from the CNS to a target organ (muscle or a
gland). Follow each nerve as much as possible from the trunk to its peripheral
attachment. The central nervous system (CNS) attachment of each nerve will
probably not be visible, but the student can find the information about the
attachment of the nerves to the CNS (brain and spinal cord) in the available
dissector and anatomy atlas.
Ganglia are groups of many neuron cell bodies protected in a tough
connective tissue pouch located in the PNS. The major locations for ganglia are:
 the posterior (sensory) root near the spinal cord where the cell bodies of
sensory neurons are located,
 a paravertebral chain of ganglia of the sympathetic (fight or flight) branch
of the autonomic nervous system,
 collateral ganglion, as part of complex plexuses of nerves in the trunk
(also sympathetic),
 terminal ganglia of the parasympathetic (rest and digest) system. If
these are visible they will be seen as part of an internal organ.
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Cranial Nerve
Cranial Nerves
Origin or
Peripheral
Insertion
attachment
(attachment site
in brain)
Visible Location
Olfactory (I)
Optic (II)
Oculomotor (III)
Trochlear (IV)
Trigeminal (V)
(ophthalmic
branch)
Trigeminal
(maxillary branch)
Trigeminal
(mandibular
branch)
Abducens (VI)
Facial (VII)
Vestibulocochlear
(VIII)
Glossopharyngeal
(IX)
Vagus (X)
Accessory (XI)
Hypoglossal (XII)
Selected Nerves of the Cervical Plexus
Cervical Nerve
Rami
Ansa cervicalis
Target
Phrenic
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Selected Nerves of the Brachial Plexus
Brachial Nerve
Rami
Musculocutaneous
Target
Axillary
Radial
Median
Ulnar
Long Thoracic
Selected Nerves of the Lumbar Plexus
Lumbar Nerve
Rami
Iliohypgastric
Target
Ilioinguinal
Lateral femoral
cutaneous
Genitofemoral
Obturator
Femoral
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Sacral Plexus
Rami
Target
Autonomic Ganglia
Specific Location
Incoming Nerve
Sacral Nerve
Superior gluteal
Inferior gluteal
Sciatic
*Tibial
*Fibular
Posterior femoral
cutaneous
Pudendal
*branches of the sciatic nerve.
Ganglion
Celiac
Superior mesenteric
Inferior mesenteric
NOTES:
1.
Describe the pathway of the sympathetic trunk:
2.
Describe the greater and lesser splanchnic nerves:
3.
Describe the branches of the vagus nerve:
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