Conscious and unconscious actions

The autonomic nervous system responsible for regulating the functions of internal organs and glands, especially the heart, stomach, kidneys and pancreas. Somatic nervous system consists of two basic components: sensory and motor systems. Information about the external world perceived by the senses, e.g. eyes, which have special receptor cells. Other similar cells perceive the signals of pain, touch and temperature of the skin. The signals from these receptors are transmitted to the CNS via sensory nerve fibers. A set of signals, the intensity of which reaches millions of pulses per second gives us the necessary information about the external world. With team CNS via motor nerve fibers go to the muscles.
Sensitive nerve fibers information arrives in the CNS, and from there, commands are sent to one or other muscles via motor nerve fibers.
And sensitive and motor nerve fibers are part of the sensory and motor neurons. All neurons consist of a cell body and a number of leading fibers. Sensory and motor fibers of the CNS - the long fibers of the respective neurons. Cell bodies of sensory nerve fibers located near the head or the spinal cord, and motor neurons within the brain or spinal cord.
Motor and sensory fibers that carry messages from a particular organ or area of the body and back, is collected in the beam - nerve. It is believed that different nerves "feed" a specific area or organ. In General, moving away from the Central nervous system 43 pairs of nerves: 12 pairs of cranial nerves from the brain and 31 pairs on both sides of the spinal cord.
Cranial nerves nourish the sense organs and muscles inside the skull, although a very important nerve of this kind - wandering - responsible for the digestive organs, heart and lung Airways. Some cranial nerves (e.g. optic nerve of the eye) are composed of only sensory fibers.
Spinal nerves extend from the spinal cord and contain both motor and sensory fibers. They nourish all parts of our body below the neck. Each nerve is attached to spinal cord by two roots, one of which contains the motor and the second sensory fibers.
Thus, the PNS serves only to transmit sensory and motor messages between the Central nervous system and the muscles, glands and sense organs. Peripheral nervous system practically is not involved in the analysis of sensory signals or the formation of motor signals, since these actions are carried out by the Central nervous system.