|Example of several unipolar neurons from a nerve ganglion of a
velvet worm (a primitive arthropod). The neurons were stained
for serotonin immunoreactivity, and photographed using a
confocal microscope, with multiple images overlaid and color-
coded according to depth. Arrows mark the peripherally located
cell bodies of several neurons, whose neurites extend into the
central neuropil (np), where they ramify in a way too complex to
be discernable. Scale bar: 50 micrometres.| A unipolar neuron is
a type of neuron in which only one protoplasmic process
(neurite) extends from the cell body. Most neurons are
multipolar, generating several dendrites and an axon. Unipolar
neurons that begin as bipolar neurons during development are
known as pseudounipolar neurons. Unipolar neurons are common in
insects, where the cell body is often located at the periphery
of the brain and is electrically inactive. These cell bodies
often send a single neurite into the brain; however, this
neurite may ramify into a large number of b