NERVOUS SYSTEM

The Central Nervous System consists of the the Spinal Chord and the Brain.

The spinal Chord conducts sensory information from the Peripheral Nervous System to the brain.

It also conducts motor information from the brain to other effectors such as: Skeleton muscle, Cardiac Muscle and Smooth muscle.

It serves as a minor reflex center.


BRAIN

The brain receives sensory inputs form the spinal chord as well as its own nerves.

 It devotes most of its volume to processing its various sensory inputs and inititating appropriate and coordianted motor outputs.

Peripheral Nervous System

Extends out of the CNS. The main function of the PNS is to connect the CNS to limbs and organs. Unlike the CNS, the PNs is not protected by bone or blood-brain barriers, which leaves it exposed to toxins and mechanical injuries. The Pripheral Nervous System is dived into the Somatic and Autonomic Nervous Systems.

Somatic Nervous System is apart of the PNS that is associated with the voluntary control of th body movement through the action oft he skeleton muscles, and wtih reception of external stimuli that helps keep the body in toutch with its surroundings. ( I.E, hearin, touching, smelling)

The systems includes all neurons connected with muscle, skin, and sense organs. The Somatic system consusts of efferent nerves responsible for sending brain signals to muscle contraction.

 

Autonomic Nervous System is apart of the Peripheral Nervous System that acts as a control system, maintaining homostasis in the body. These activities are performed without conscious control or sensation. The Autonomic system controls digestion, heartrate, salivation, resporation rate, perspiration, diameter of the pupils, micturition (uriniation), and sexual arousal. Some actions scuh as breathing are in tandem with the conscious mind.  

For More information: http://www.emc.maricopa.edu/faculty/farabee/BIOBK/BioBookNERV.html