Neuron Structure

Neuron Structure

Neurons constitute the basic unit of the nervous system, and are also considered as the basic building blocks of the same. These specialized cells are responsible for receiving and transmitting information. This article provides some information about the structure of the neuron.
Bodytomy Staff
Neuron Structure
Whenever a body organ and the brain needs to communicate with each other, the information is transmitted and received with the help of neurons. This communication network works, depending on their structure and types. They are the cells of the nervous system that make the nervous tissues of the brain, the spinal cord, and the rest of the nerves of the nervous system. These also form all types of nerves, leading to and from these organs, and help in giving meaning to our senses. These cells, in addition, act as processing units of the brain.

The Structure

A neuron or nerve cell can be differentiated into three parts: cell body, an axon, and dendrites. It consists of a nucleus, cytoplasm, golgi body, and other organs necessary for the normal functioning. These vary in size, shape, and characteristics, depending on the role and function that they perform.

Axon: An axon is a projection from the cell body, and it is a few millimeters to one meter in length. It is covered with the myelin sheath, and is responsible for conducting the messages from its cell body to other nerve cells and body cells such as muscles (connective tissue).

Dendrite: A dendrite is the short protrusion from the cell body of the nerve cell. It carries messages from the other nerve cells and human body cells, to its own cell body, where it is processed or transmitted to the next one in the network.

There are three types of neurons: sensory (afferent), motor (efferent), and interneurons. They have the ability of communicating with other cells using chemicals or electrical discharge. Information is exchanged at a junction called synapse, with the help of neurotransmitters. It is a place where single or multiple nerve cells and a muscle meet to exchange information. Axon of one of them transfers information from its cell body to the dendrites of the other, which in turn carries it to its cell body. However, when it comes to the communication between sensory and motor nerve cells, it is the interneuron that acts as the postman and relays the messages.

Classification

Not all of them are same in structure. If one goes by their structure, the main characteristic that is used in separating one type from the other is the number of protrusions or processes (axon and dendrites) extending from the cell body of a nerve cell.

Unipolar Neurons: In these, a single protrusion extends from the cell bodies, and divides into two branches very close to it. These branches act as the axon and the dendrite for these nerve cells. This type of nerve cell describes the sensory structure, and its function is to carry messages from the sense organs of the body to the nervous system, which are then acted upon by the brain.

Bipolar Neurons: These are characterized by the presence of a dendrite and an axon protruding directly from the cell body. A part of the pathway for sight, smell, hearing, taste, and vestibular functions, these specialized sensory cells facilitate the transmission of these senses.

Multipolar Neurons: The cell body of these nerve cells, as the name suggests, has many protrusions. One of them acts as an axon, whereas the rest act as dendrites. These carry messages from the central nervous system to the muscles which convert it into an action.

The brain alone contains 100 billion cells, in addition to the different kinds of cells in the human body. It is considered as the seat of thought, and is the master of the human body and actions. It registers all the emotions and bodily pains felt by an individual, and is still a sacred and secret place. It stores them, and if needed recalls them too.

Disclaimer: This Bodytomy article is for informative purposes only, and should not be used as a replacement for expert medical advice.