The figure shows exmples of the most common types of neurons. Axons are shown in blue and dendrites in red. The nerve impulses proceed from top to bottom.
From the point of view of their structure and especially of their extensions, the following types of neurons are found:
Unipolar neurons have a cell body and one axon. These neurons are mainly sensory receptors. Examples: sensory cells of the retina and sensory cells of the olfactory mucosa.
Bipolar neurons – have a cell body, one dendrite and one axon. Found mainly in sensory structures of the retina and olfactory mucosa.
Pseudounipolar neurons – have a cell body and one extension formed by two continuous parts, one behaves as a dendrite and the other as an axon. They are typically found in the sensory ganglia placed along the the spinal cord and are responsible for conducting nerve impulses of touch, pressure, pain, heat, and cold from the periphery toward the central nervous system.
Multipolar neurons have a cell body, several dendrites, and one axon. They are the majority of neurons of the nervous tissue and are the predominant type of the central nervous system.
