Question

What is the basic cell of the nervous system?

Answer 1

The neuron.

Explanation:

Neurons are the basic nervous system cell, and they are highly specialised for this job. They have adapted to be very efficient at sending electrical impulses (messages) through the body. In a way, neurons are like messengers for your body. They take signals from the brain and deliver them to the rest of the body (or vice versa).

In terms of their structure, there are many similarities between neurons and other cells. They have cell membranes (these are essential for separating positive and negative ions which are responsible for electrical impulses), nuclei (containing genetic information) and many other standard organelles but neurons also have axons and dendrites.
The axon is like a long tail and it sends messages while the dendrites are spiky extensions from the cell body that receive messages from other cells (you can read about how they do this here ).

Something that is worth noting is that, unlike other cells, neurons in the cerebral cortex (outside of the brain) aren't replaced. This means that any that are damaged will have to be repaired or the nervous system will lose cells. (This is why after initial growth, the brain tends to decrease in size).

Hope this helps, please let me know if I can do anything else or if anything is unclear:)