Transcript Chapter 14

Peripheral Nervous System
Chapter 14 – Lecture Notes
to accompany
Anatomy and Physiology: From Science to Life
textbook by
Gail Jenkins, Christopher Kemnitz, Gerard Tortora
1
Chapter Overview
14.1 PNS Connective Tissues
14.2 Cranial Nerves
14.3 Spinal Nerve Branches
14.4 Reflexes
14.5 SNS and ANS
14.6 Anatomy of the ANS
14.7 ANS Signal Transmission
14.8 Sympathetic and Parasympathetic Divisions
of ANS
14.9 ANS Reflex Arcs
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Essential Terms
Peripheral Nervous System (PNS)
 all parts of nervous system that are not brain and
spinal cord
Ganglia
 collections of neuronal cell bodies
Somatic nervous system (SNS)
 associated with voluntary or conscious activities
and body sensations
Autonomic nervous system
 operates without conscious control
Nerve
 hundreds to thousands of PNS axons plus
associated connective tissue & blood vessels
bundled into functional organ
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Introduction
Peripheral nervous system divided into
somatic nervous system and autonomic
nervous system

Somatic nervous system is divided into
sensory and motor portions
Autonomic nervous system has
sympathetic and parasympathetic nervous
divisions and innervates enteric plexuses
•
•

both sympathetic and parasympathetic
divisions have motor and sensory components
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Nerves
cranial nerves



emerge from brain
12 pair
spinal nerves



emerge from spinal cord
31 pair
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Concept 14.1
PNS Connective Tissue
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PNS Connective Tissue Layers
endoneurium
1.

wraps individual axons
perineurium
2.

wraps axons bundled into fascicles
epineurium
3.



wraps entire nerve
fuses with dura mater of CNS
blood vessels within perineurium and
epineruium
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Figure 14.1a
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Figure 14.1b
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Concept 14.2
Cranial Nerves
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Cranial Nerves
12 pair
numbered from anterior to posterior
emergence from brain
sensory nerves



I and II

mixed nerves



III to XII
both sensory and motor neurons
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Figure 14.2
12
Cranial Nerves
I.
II.
III.
IV.
V.
VI.
VII.
Facial
VIII.
Vestibulocochlear
IX.
Gossopharyngeal
X.
Vagus
XI.
Assessory
XII.
Hypoglossal
Olfactory
Optic
Oculomotor
Trochlear
Tigeminal
Abducens
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Cranial Nerves
Sensory neurons

cell bodies located in ganglia outside brain
Motor neurons

cell bodies in nuclei within brain
Cranial Nerves III, IV, XI, and XII

primarily motor
Cranial nerve V

largest of cranial nerves
Cranial nerve III, VII, IX, X

both somatic and autonomic motor axons
Cranial nerve VIII

primarily sensory
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Figure 14.3
15
Figure 14.4
16
Figure 14.5
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Figure 14.6
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Figure 14.7
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Figure 14.8
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Figure 14.9
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Figure 14.10
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Figure 14.11
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Figure 14.12
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Table 14.1 pt 1
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Table 14.1 pt 2
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Table 14.1 pt 3
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Table 14.1 pt 4
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Table 14.1 pt 5
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Table 14.1 pt 6
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Table 14.1 pt 7
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Concept 14.3
Spinal Nerve Branches
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Spinal Nerves


31 pair
numbered from superior to inferior
associated with vertebral regions

8 pair of cervical nerves

12 pair of thoracic nerves

5 pair of lumbar nerves

5 pair of sacral nerves

1 pair of coccygeal nerves
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Figure 14.13
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Spinal Nerve Branches
posterior ramus


deep muscles and skin of dorsal trunk
anterior ramus


limbs and skin of lateral and ventral trunk
meningeal branch


supplies vertebrae, vertebral ligaments,
blood vessels of spinal cord and meninges
rami communicans


autonomic nervous system
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Figure 14.14
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Spinal Nerve Plexuses
cervical plexus


Figure 14.15
brachial plexus


Figure 14.16
lumbar plexus


Figure 14.17
sacral plexus


Figure 14.18
intercostal nerves


spinal nerves T2-T12
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Table 14.2
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Figure 14.15
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Table 14.3
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Figure 14.16a
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Figure 14.16b
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Table 14.4
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Figure 14.17a
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