The Nervous System of all the systems in the body is attributed to be the most complex and delicate system. The kernel of the nervous system is the brain. It sends and receives messages via a network of nerves.
The tissue of the nervous system is composed of two types of cell, which are neurons and glial cells. The neurons help in transmitting nerve messages. The neuron is the main operational unit of the nervous system. They vary in their size and shape and the typical neuron is divided in three parts. The Dendrites are responsible for receiving information from other cells and then transmit the message forward to the cell body. The cell body has a nucleus, mitochondria and other organelles which are usually present in the eukaryotic cells. The axon then transmit message away from the cell body.
Basically three types of neurons occur. Firstly, the Sensory neurons have a long dendrite and short axon. They carry messages from sensory receptors like the skin to the central nervous system. Secondly, Motor neurons, which have a long axon and short dendrites; they carry messages from the central nervous system to the muscles or the glands. Moreover, the Interneuron cell is located in the central nervous system where they are responsible for transmitting sensory messages between neuron.
Constant internal environment and monitoring of external environment is coordinated by the nervous system and the endocrine system. The three basic function that a nervous system typically performs are, firstly to receive sensory messages from both the internal and external environment, secondly, it helps in integrating the inputs , and lastly it helps to respond to the sensory inputs receive by the stimuli.
The Sensory Input Receptors are also considered part of the nervous system................
