The units which make up the nervous system are called nerve cells or neurons. So, neurons are the structural and functional unit of the nervous system. Neuron is an elongated branched cell having three components ~ Cell body, Dendrites and Axon.
Fig.1
Dendrites of a neurons collect information from the receptors and pass it to the cell body in the form of electrical impulse. From the cell body impulse passes along the Axon to its end. At end of the Axon, the electrical impulse results in the release of certain chemicals ( chemical neurotransmitters). These chemicals cross the gap (synapse) between the endings of the Axon and Dendrites of the next neuron and start a similar electric impulse in the Dendrites. Thus information received travels along the neurons of a nerve to the effector muscles or gland. On reaching to the desired muscle or gland, Axon endings from Neuromuscular junction (synapse between Axon endings and muscle cells) through which information delivered from neuron to muscles or glands.
(i) End of Dendrites acquire information.
(ii) The electrical impulse is converted into a chemical signal at the synapse.
