The nervous system refers to the bodily system made up of the brain, nerves, spinal cord, ganglia and other receptor organs that receive and interpret stimuli.
All living organisms are aware of the changes occurring in their external environment, like change in light, temperature, sound, motion, and smell. Certain internal changes in organisms include the position of head, limbs and other internal organs. When it comes to the survival of any living organism, it depends on how well they react to stimuli or changes in their environment. Faster response to stimuli means better survival rate.
As communication from one cell to another is very slow and insufficient for survival, a system was involved that led to faster response to stimuli. This system was known as the nervous system, which could instantly transfer electrical signals from one part of the body to another. There are two kinds of nervous systems namely, diffuse and centralized.
The diffuse nervous system has no brain, and neurons are scattered across the organism. While the centralized nervous system includes a fully developed brain and spinal cord, where impulses are carried out by nerve fibres, from the brain to the spinal cord.
Main Article: Human Nervous System (Structure, Function & Parts)
Frequently Asked Questions on Nervous System Definition
Define nervous system.
The nervous system is defined as the system of the body that includes the brain, spinal cord and sensory organs that receive, interprets and responds to internal and external stimuli.
What are the three common nervous system disorders?
Alzheimer’s disease, Parkinson’s disease, multiple sclerosis and epilepsy are some common nervous system disorders.
- Central Nervous System – Overview, Parts, and its Functions
- Peripheral Nervous System – Definition, Parts and Functions
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