A complicated system of nerves and cells which can transport correspondence from brain to the spinal cord and to different region of a body is generally called Nervous System.
This system can be divided into two main parts. Central system and Peripheral system are the main parts of this system. By the brain and spinal cord the central system is built up and Somatic and the Autonomic systems make the Peripheral System.
A brief account:
Basically the name of this system has been adopted by the nerve itself and first came to notice by the ancient Romans, Egyptians and many more, but the depth analysis was not known until the discovery of advanced microscopes which further helped in investigating the basic units involved.
Nerves are basically cylindrical bundles which are constituted by fibers, their origin occurs from the multi functioning organ i.e. brain and the essential physical supporter normally called backbone but specifically it is the spinal cord. And the nerves after emerging from them are further diversified into numerous parts of our body.
Spinal cord and brain built the central system. Mainly built up by nerves peripheral system’s main aspect is to transfer information’s back to human brain. This system can take the blame for the functions which happens in a human body without any consciousness, like the beats of the heart or the digestion works. Peripheral System achieves its own smooth operation by dividing into two pieces like sympathetic and parasympathetic systems respectively. These actions are contrasting actions and it creates a balance system and checking procedure. The system takes electrical compulsion to converse external condition to human brain, the electrical compulsion tours with a length of neurons and other system cells. These cells work on information from the sensor nerves and works on an action within a mile second. These compulsions have 250 miles per hour speed but the other system takes a long time to respond with appropriate hormones such as endocrine system.
Basic structure of nerves
As per the analysis of highly sophisticated instruments, nerves consists of
• Axon of neuron
The neuron is assigned as the basic unit from which nerves are composed of, but it’s not that whole of a neuron is contained in the nerve but their cell body is generally found to be consisted in brain, peripheral ganglia.
This system is possessed by almost all sorts of animals, advanced than sponges. Even these sponges and various unicellular organisms which do not possess nervous system, are believed to persist on the basic mechanism of signaling which is itself the precursor to neurons.
In other varied animals like jellyfish and hydra they consist of an even complex system which is based on diffused network of insulated cell units. The most ancient form of the nervous system that was about 500 years back is believed to be constituted by the bilateral animals.
This system contains two different types of cells named such as Neurons and glial cells.
• Neurons :
Neuron is the essence of this system; this is the correct caption so as to define the dependency of nervous system on neurons often said as nerve cell.
Synapse the integral entity possessed by nerve cells which even differentiates them from other kind of cells, as this entity is responsible for signaling mechanism, these serve as a membranous juncture associating molecular machinery so as to facilitate quick message transmission of both the signals i.e. chemical and electrical. Basic possessions of a neuron are axon, protoplasmic protrusion which further enables various synaptic connections so as to facilitate faster transfusion, the axons possessing transport in bundles are collectively known as nerves.
Neurons are not confined to a single type but instead it differs in a great range in organisms like humans which enables even different functions. The differed inclusions are sensory neurons which converts physical stimuli into signals next are motor neurons which perform conversion of signals into our various muscles.
• Glial cells:
Glial cells are a kind of non-neuronal cells that supply nutrition and a basic support to this system by taking part in the action of signal transmission. Besides, glial cells, derived from the Greek word “glue” are important enough to maintain homeostasis in human nervous system. According to the medical report in case of human brain the total number of glial is equally proportionate to the number of neurons presented in the total volume of the brain. This kind of cell is featured with some biological actions like- to give a backing to neurons by holding them properly, to nourish neurons with the essential stuff, demolishing the pathogens to exterminate the dead neurons, to endow the axons of neurons with the proper guiding signals to their target and finally to insulate neurons though electric means. Another very important task of glial cells is to wrap the axons by procuring a healthy surface of fatty substance called myelin and to arrange for the electrical insulation that permits them to transfer action potentials quite swiftly.
Role of nervous system
The most foremost function associated with nervous system is conveying the integrated sort of signals from one cell to another and further from one body part to the other.
Various paths involved by which a cell can convey signal to the other
• By absolving chemicals precisely known as hormones, into inter circulated system so they can be transported to target sites by diffusion.
• The broadcasting sort of signalling which actually conveys the message by the electric impulse which is then transfused into the other neuron’s axon and further by synaptic connections the signal reaches the destined target and the desired action is performed.
The ability of transfusing the signal possessed by neurons across such network is really unbeatable as it is 100 meter per second.
Usage of sensory receptors is the basic role involved as by this the information about environment is taken and as per it actions are assisted in order to maintain an overall balance of our body and thus controls it efficiently.
The evolution in the nervous system has enabled various species to facilitate the advanced perceptions. The nervous ailments, if any, need to be countered in a definite way with proper medications.