Concepts of Human Anatomy & Physiology   5/e   Van De Graaff/Fox
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I. Introduction to the Peripheral Nervous System

Concept: The peripheral nervous system consists of all of the nervous tissue outside the central nervous system, including sensory receptors, nerves and their associated ganglia, and nerve plexuses. It provides a communication pathway for impulses traveling between the CNS and the rest of the body.

II. Cranial Nerves

Concept: Twelve pairs of cranial nerves emerge from the inferior surface of the brain and pass through the foramina of the skull to innervate structures in the head, neck, and visceral organs of the trunk.

III. Spinal Nerves

Concept: Each of the 31 pairs of spinal nerves is formed by the union of a posterior and an anterior spinal root that emerges from the spinal cord through an intervertebral foramen to innervate a body dermatome.

IV. Nerve Plexuses

Concept: Except in the thoracic nerves T2 through T12, the anterior rami of the spinal nerves combine and then split again as networks of nerves referred to as nerve plexuses. There are four plexuses of spinal nerves: the cervical, the brachial, the lumbar, and the sacral. Nerves emerging from the plexuses are named according to the structures they innervate or the general course they take.

V. Reflex Arc and Reflexes

Concept: The conduction pathway of a reflex arc consists of a receptor, a sensory neuron, a motor neuron and its innervation in the PNS, and an association neuron in the CNS. The reflex arc provides the mechanism for a rapid, automatic response to a potentially threatening stimulus.

VI. Development of the Peripheral Nervous System

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