Neuron

Neurons (also spelled neurones or called nerve cells) are the primary cells of the nervous system.

Neurons of the brain

The nematode worm (Caenorhabditis elegans) has 302 neurons. Scientists have mapped all of the nematode's neurons.

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The human brain has about 100 billion (10^{11}) neurons and 100 trillion (10^{14}) connections (synapses) between them.

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