The main function of the nervous system is to carry the information or signal from one part of the body to the other.The term “nervous system” is derived from the word “nerve”. Nervous system functions are the most important feature which takes part between the brain and spinal cord. The brain and the spinal cord containing all the cranial and spinal nerves respectively act as central processing unit and bus (data transmitting route). Here the information which is fetched by one ends of the nerves which are located at different external sense organs of the body and are transmitted in form of a certain chemical to the brain for processing.
Nervous system as a processing unit:
From the above paragraph we have already come to know that nervous system functions is not a function which occurs independently, but it is the system which we can compare with a processing unit like computer. Like any of the computer the nervous system basically deals with input and output signals. Here by the word “input signals” we mean the external stimuli received different autonomous activity response of organs inside our body and “output signals” generally is the outcomes of the various inputs which are released in the form of hormones which are send through the nerves.
Different constituents of nervous system:
Nerve is the collection of tissues collecting information or signal. As we know this system is solely dependent on various constituents of it, so it can be divided into two parts. For the vertebrates including human the nervous system function is processed by two main parts:
• CNS – Central Nervous System
• PNS – Peripheral Nervous System
The Central Nervous System (CNS) and the Peripheral Nervous System (PNS) are two individual systems but they work together for proper running of nervous system functions. In a greater aspect of scientific viewing the main function the nervous system is to maintain the control over each and every part of the body. CNS and PNS are divided according to their structures and different functions.
Central Nervous System (CNS)
• Structure = Brain and Spinal cord
• Function = Accumulation and control of the whole system
It has been proved that CNS is the largest part of the nervous system function containing the brain and the spinal cord. Here the brain is located in the head within the skull and the spinal cord is fitted inside the spinal cavity which is the backbone of all the vertebrates. While talking about the vertebrates we must not forget that the invertebrates also do have the nervous system function working within their bodies. In their cases like of unicellular animals, sponges the nervous system works as point function or cell-to-cell mechanism. Here the information travels by the neurotransmitter.
Peripheral Nervous System (PNS)
• Structure = Cranial nerves and spinal nerves
• Function = To communicate between the CNS and other parts of the body
Function of cells in the nervous system:
The two main cells of the body which take part in the nervous system function are neurons and glial cells. Neuron is called the nerve cell which can be differentiated from the other cells both structurally and functionally. The main function of the neuron is to transmit signals by the help of synapse. The glial cells are present in equal number with the neurones and the main function of it is to support the neurones and supply nutrients to the cell so that nervous system functions properly.
- constituent parts of the nervous system in animals
- brain system
- peripheral nervous system
- الجهاز العصبي
- merkezi sinir sistemi