Page 337 - Atlas of Histology with Functional Correlations

FIGURE 9.2 ■ Examples of different types of neurons located in various
ganglia and organs outside the CNS.

Surrounding the neurons are the smaller and more numerous supportive cells
collectively called neuroglia. These cells form the nonneural components of the
CNS.

TYPES OF NEURONS IN THE CENTRAL

NERVOUS SYSTEM

The three major types of neurons in the nervous system are multipolar, bipolar,
and unipolar. This anatomic classification is based on the number of dendrites
and axons that originate from the cell body.

Multipolar neurons. These are the most common type in the CNS and
include all motor neurons and interneurons of the brain, cerebellum, and
spinal cord. Projecting from one side of the neuron cell body are numerous

branched dendrites in contrast to a single axon on the opposite site.
Bipolar neurons. These are less common and are purely sensory neurons.
In bipolar neurons, a single dendrite and a single axon are associated with the
cell body. Bipolar neurons are found in the retina of the eye, in hearing and

equilibrium region organs of the inner ear, and in the olfactory epithelium of

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