Nervous System 2

The Peripheral Nervous System

In this lab you will view some of the structures of the peripheral nervous system.

Begin by clicking on the following:

    Anterior Spinal Cord with Spinal Nerves

Locate the following cervical nerves on the right:

    C4

    C5

    C6

    C7

    C8

Follow the course of the nerves laterally. You will see that they combine to form a structure called the brachial plexus. All of these nerve roots are involved in forming this plexus.

Locate the following:

    Radial Nerve Right

    Median Nerve Right

    Ulnar Nerve Right

Rotate the view 20 degrees to the right using the thumbwheel.

Locate the Musculocutaneous Nerve Right

These are all what are known as terminal branches of the brachial plexus. For example the median nerves comes off of the plexus and continues down the middle of the arm ending in the hand. This is the nerve that is involved in carpal tunnel syndrome.

Click on the following:

    Inferior portion of spinal cord

Locate the following:

    Sciatic Nerve Right

    Femoral Nerve Right

    Obturator Nerve Right

The sciatic nerve continues down the posterior portion of the leg. It can become irritated and painful in a condition called sciatica.

Notice how the inferior portion of the spinal cord ends in what is called the cauda equina or "horse's tail." Use you textbook to locate the cauda equina and conus medullaris. The conus medullaris is a cone shaped structure that marks the inferior end of the spinal cord.

Locate the thoracic portion of the sympathetic trunk left. This is part of the autonomic nervous system. The autonomic nervous system consists of 2 parts; the sympathetic and parasympathetic divisons. The sympathetic nervous system is also known as the thoracolumbar division because it is located near these parts of the spinal cord. The parasympathetic nervous system is known as the cranial sacral division for the same reason.

This concludes the lab.