Nervous system
The nervous system, or so-called neurotransmitter, is one of the most important organs of living organisms. It is present in all organisms, from cell monocytes to mammals, consisting of a group of simple circuits between small groups of neurons in monocytes, The nervous system is complicated with the rise in the ladder of evolution, until the most complex and efficient types of neurotransmitters in humans.
Definition of the nervous system
The nervous system is defined as an internal network of connections found in the body of organisms, which adapts the body to the environmental changes that surround it.
Sections of the nervous system
The nervous system consists of two main sections where each department is responsible for performing several specific functions.
- The central nervous system.
- peripheral nervous system.
How the nervous system works
The nervous system consists of billions of specialized cells known as neurons or neurons, which are grouped together in the form of cords called nerve cords. These nerves travel in many ways to transmit information quickly to all members of the body, as well as to react to a person as a result of exposure to certain situations , And thousands of complex processes within the body does not take a part of the second, the nerve cells are present in a member of the senses such as the ear and hands, and the nervous system works through the following way:
- Specialized neurons, known as receptors, translate what people feel into nerve signals known as nerve impulses.
- Neuronal impulses are transmitted through nerve fibers at 1 to 90 m / s, to the brain and spinal cord.
- Neurotransmitters in the brain receive nerve impulses, analyze them and interpret them and choose the right decision and reaction to take.
- The brain sends new nerve impulses transmitted through motor neurons to the receptors, such as in the muscles and glands to respond to the orders of the brain.
- The brain also sends its messages to the heart to increase the pulse and contractions and thus increase blood flow.
An example of how the nervous system works
When the human sees the tiger, the receptors in the eyes respond to the light rays. The vision reflects the translation into nerve impulses that move to the neurons in the brain, which translates the vision of the tiger into fear and sends other impulses to the recipients to execute the brain commands. For example, To help the human escape away from danger, as the brain sends a message to the heart to increase the pulse and the flow of more blood in the muscles of the swimmers to accelerate the ability to run.