A nerve cell is the smallest functional unit of the nervous system.
Nerve cells are usually shaped like trees. From the round, pyramidal or spindle-shaped cell body the dendrites (greek: dendrites = tree-like) branch out like the top of a tree and the single axon travels out like the trunk.
The dendrites receive information from other nerve cells and pass it down to the cell body where the information is processed.

This information is then passed along through the nerve cell’s trunk which is called axon (greek: axon = axis). The length of this extension differs depending on the kind of nerve cell. It can span from a few millimeters up to one meter. For instance, it can span from the spinal marrow to the foot.
This extension branches out at the end, comparable to a long trunk of a tree which passes into a widely ramified root system.

In the brain, nerve cells constantly exchange information in the form of electric currents. Here the dendrites are the signal recipients. The axon relays the signals.Transmission of information in the nervous system