The nervous system has two major divisions: the central and the peripheral.
The nervous system begins to form within a few days after the fertilized egg implanted in the uterus of the mother.
It is so important that it is the first body part that is formed and from that moment, begins to perform most of its functions and continues to grow and develop.At about the seventh week of pregnancy, the brain and spinal cord that are its main parts, are easily recognizable by ultrasound.
The nervous system is composed mainly of the brain, which is the "engine of the body", the spinal cord and all the millions of nerves that reach every part of the body.
This system is very complex, to perform many functions in turn divides into two "systems" that are:
-The Central Nervous System (CNS) consists of the brain and spinal cord.
-The Peripheral Nervous System (PNS ), composed of a vast network of nerves that leave the central nervous system and are branching out to the body.
These two systems work in perfect coordination, peripheral nervous system is responsible for carrying messages to the central nervous system and the Central sends his instructions through the peripheral and record what happens inside and outside the body.
