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Peripheral Nervous SystemChapter 14 – Lecture Notes

to accompany

Anatomy and Physiology: From Science to Life

textbook by

Gail Jenkins, Christopher Kemnitz, Gerard Tortora

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Chapter Overview14.1 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 TermsPeripheral 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 sensationsAutonomic nervous system

operates without conscious controlNerve

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 Layers1. endoneurium wraps individual axons

2. perineurium wraps axons bundled into fascicles

3. epineurium 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

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Cranial Nerves

I. Olfactory

II. Optic

III. Oculomotor

IV. Trochlear

V. Tigeminal

VI. Abducens

VII. Facial

VIII. Vestibulocochlear

IX. Gossopharyngeal

X. Vagus

XI. Assessory

XII. Hypoglossal

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Cranial NervesSensory neurons

cell bodies located in ganglia outside brainMotor neurons

cell bodies in nuclei within brainCranial Nerves III, IV, XI, and XII

primarily motorCranial nerve V

largest of cranial nervesCranial nerve III, VII, IX, X

both somatic and autonomic motor axonsCranial nerve VIII

primarily sensory

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Figure 14.3

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Figure 14.4

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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