Neuroanantomy of Caenorhabditis elegans

 

 Each C. elegens has exactly 302 neurons (cells), with about 5000 chemical synapses (which pass an electrical or chemical signal from one neuron to another),  2000 neuromuscular junctions (where nerves and muscle fibers meet) and 975 gap junctions (which allows various molecules, ions and electrical impulses to directly pass through a regulated gate between cells. By comparison, humans have about 86 billion neurons, as many as 100 trillion synapses and a large number of  gap junctions.The interconnection of neurons through these synapses form the network which control all the actions which C. elegens can possibly undergo. That is, the way in which the synapses and their interconnections are the coded instructions -- the program -- for the automatic performance of  all the material functions of C. elegens.

The above illustration is that of all 302 neurons and their interconnections between the four kinds of cells C. elegens has. It is, in effect, the brain of C. elegens complete with individual axions protruding from it for sensory input signal and output functional signals to various parts of its body. And the network is exactly in the same in each and every C. elegens.  

And, the human brain has the same kind of neural network as does C. elegans performing the same functions.