The elements

"Working elements" of the nervous system are the millions of interconnected cells called neurons that perform the same function as the wires in complex electrical machine. Neurons receive signals in one part of the nervous system and transmit them to another part of the signals can act on other neurons or to cause a certain action, 5 for example, the contraction of muscle fibers.
The cells are very fragile cells that can easily be damaged or destroyed as a result of trauma, infection, pressure, chemical exposure or lack of oxygen. Moreover, since the destroyed neurons do not regenerate, such violations can have serious consequences. The nervous system is divided into two interrelated parts - the Central nervous system (CNS) consisting of brain and spinal cord, and peripheral nervous system (CNS), which includes all nervous tissue outside the Central nervous system. And peripheral and Central nervous systems consist of several components.
From the peripheral nervous system two divisions: the external, or somatic, nervous system and internal vegetative nervous system.
Somatic system performs two functions, namely: collecting information from the senses and sends it to the Central nervous system; transmits signals from Central nervous system to skeletal muscles in response to the received information, thereby predetermining the movement of the body.