The nervous system is extremely complex and highly sophisticated system which is containing a network of special cells called neurons. It is the control center of the body. The primarily functions of nervous system are to coordinate all activities of the body and enable the body to respond and adapt to changes that occurred both inside and outside the body.
Commonly, from the anatomical standpoint, the human Nervous system can be broken up into major tow parts which is called Central Nervous System(CNS) and Peripheral Nervous System(PNS).
The CNS made up of brain and spinal cord. The brain is found within the cavity of the skull. The spinal cord is the link between the brain and the nervous in the rest of the body and encased in the cavity of the vertebral column. The peripheral nervous system comprise every things outside the brain and spinal cord. PNS transfer information into the CNS and carry signal out of the CNS.
At the cellular level, neural tissue consist of tow major type of nerve cells which is call neurons (nerve cell) and neuroglial cell. The glial cells protect, provide physical support, supplying nutrients and removing waste materials of the neuron. Neuroglial cells are not directly involved in processing of information but their functions are vital for normal activities of the brain.
Neurons are the basic functional unit of nervous system and play a vital roles in transmission of impulses. They have the ability to process and transmit information.
The neuron structurally has three parts: Axon, Dendrites and Cell body
Axon is the longest extension of cell body and recognizable by its length. Axon typically convey an output signal to other neuron or by other means, axon propagate the nerve impulse away from the soma. A single axon begin from a cone shape structure of cell body where the axon emerges and known as axon hillock. The impulses accumulated at the axon hillock then transmit it along the axon. Eventually, the axon terminates in axon or synaptic terminals.
Dendrites makes the input system of neurons. They are short brunches that come off of the cell body. They connect the neuron to the other surrounding neurons and receive signals in the form of neurotransmitters and conduct it towered the soma or cell body.