The nervous system is made up of billions of cells called the nerve cells or the neurons. They are responsible for efficient communication within the organism, involving receiving and sending impulses or messages tothe brain or spinal cord of the central nervous system. Nerve cells are synthesized by the process known as neurogenesis
Structure
The neuron has the following important components
- Cell body : it is also known as soma. It consists of the nucleus and all the other otrganelles required by the cell for its activities. It maintains the neuron structure, provides energy etc. the cell body is bound by a cell mebrane aswell.
- Axon : a neuron has extensions that carry the nerve impulses, one of them is called the axon. The axons carries impulses towards the cell body . the axons have insulated coverings called as the mylein, that helps in the conduction . there is mainly one axon.
- Dendrons : these are the nerve extensions that impulses away from the cell . body. The dendrites receive the impulses from the axons of different cells. There could be networks of dendrites that would exist as a bunch of trees.
Types of neurons :
- Sensory neuron ;they receive the information as a stimulus that represents any change in the internal or external environment. Transmit it to the CNS where further processing can be done.
- Motor neurons : these neurons receive impulses from the CNS and generate response by the muscles , organs or glands.
- Interneurons : these neurons are present only in the CNS and connect the sensory and motor neurons. They are the most numerous of the neurons and are used for processing of the impulses within the CNS
Functions :considering the different types of the neurons the functions of the neurons are the receive of the signals from the receptor molecules, processing the information in the CNS and generating a response involving the target organs
