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Learning Objectives
- Examine the anatomy of the nervous system
- Determine the main functions of the nervous system
- Differentiate the medical terms of the nervous system and common abbreviations
- Recognize the medical specialties associated with the nervous system
- Discover common diseases, disorders, and procedures related to the nervous system
Nervous System Word Parts
Click on prefixes, combining forms, and suffixes to reveal a list of word parts to memorize for the Nervous System.
Introduction to the Nervous System
The picture you have in your mind of the nervous system probably includes the brain, the nervous tissue contained within the cranium, and the spinal cord, the extension of nervous tissue within the vertebral column. That suggests it is made of two organs—and you may not even think of the spinal cord as an organ—but the nervous system is a very complex structure. Within the brain, many different and separate regions are responsible for many different and separate functions. It is as if the nervous system is composed of many organs that all look similar and can only be differentiated using tools such as the microscope or electrophysiology.
Watch this video:
Media 8.1 The Nervous System, Part 1: Crash Course A&P #8 [Online video]. Copyright 2015 by CrashCourse.
Practice Medical Terms Related to the Nervous System
Anatomy (Structures) of the Nervous System
The Central and Peripheral Nervous Systems
Nervous tissue, present in both the CNS and PNS, contains two basic types of cells: neurons and glial cells. Neurons are the primary type of cell that most anyone associates with the nervous system. They are responsible for the computation and communication that the nervous system provides. They are electrically active and release chemical signals to target cells. Glial cells, or glia, are known to play a supporting role for nervous tissue. Ongoing research pursues an expanded role that glial cells might play in signaling, but neurons are still considered the basis of this function. Neurons are important, but without glial support, they would not be able to perform their function. A glial cell is one of a variety of cells that provide a framework of tissue that supports the neurons and their activities. The neuron is the more functionally important of the two, in terms of the communicative function of the nervous system. To describe the functional divisions of the nervous system, it is important to understand the structure of a neuron.
Neurons are cells and therefore have a soma, or cell body, but they also have extensions of the cell; each extension is generally referred to as a process. There is one important process that every neuron has called an axon, which is the fiber that connects a neuron with its target. Another type of process that branches off from the soma is the dendrite. Dendrites are responsible for receiving most of the input from other neurons.
Looking at nervous tissue, some regions predominantly contain cell bodies