- Neurons are the functional unit of the nervous system. A neuron consists of three major parts – a cell body that contains the nucleus, dendrites, which receive signals, and a long axon that carries the signal to the next cell. Length of neurons varies depending on their location. Neurons located in the central nervous system could be a few millimetres long, but some of the neurons in the peripheral nervous system could be more than a meter long. In a normal human body, there are about two billion neurons, approximately 1 billion in the brain, and another billion in the rest of the body. Glial cells are supporting cells that provide structural and functional support to the neurons and help them carry out their functions.
- For example, Schwann cells provide a covering of the axons in the peripheral nervous system.
- End of a neuron is known as synaptic terminal, which generally connects with either another neuron to continue the process of communication or to a muscle to trigger muscle action. Glial cells outnumber neurons by 10 to 50-folds.
Leave a Reply