Unipolar neuron

Recommended video: Nervous system [21:46]

Main organs and nerves of the nervous system.

Unipolar neurons, also known as 'true' unipolar neurons, possess a single process extending from the cell body. 

The nervous system is a complex web of  neurons, that are able to receive and integrate information from multiple stimuli. They then can also send messages to distant regions of the nervous system.

Neurons can be classified according to their morphology. There are four types of neurons according to this classification: unipolar, pseudounipolar, bipolar and multipolar. Unipolar neurons contain the same key structural components as other neurons: a cell body, dendrites, axon and axon terminals.

The prefix 'uni-' in unipolar means one. This is because of the singular process (sometimes referred to as a 'neurite') which extends from their cell body that then branches and then functions as axons and dendrites. 

Unipolar neurons are mostly found in central nervous systems of invertebrates. Some neurons in the human central nervous system may have a unipolar morphology. The primary example of this is unipolar brush cells in the cerebellum and posterior cochlear nucleus. Some sources may describe rod/cone cells in the retina as unipolar neurons, however they are usually classified as modified bipolar neurons. 

Unipolar neurons are not to be confused with pseudounipolar neurons that consist of one short process, which splits into peripheral and central processes.