Neurons are specialized cells which serve as the building blocks of the nervous system. Also known as nerve cells, neurons are in charge of sending and receiving signals from the brain.
The nervous system consists of an approximate 100 billion neurons. However, unlike other types of cells, neurons neither reproduce nor regenerate. Consequently, the lack of these specialized cells results in various brain-related diseases, such as Alzheimer’s disease and Parkinson’s disease.
Thus, so as to maintain the optimal condition of our nervous system, it is important that one understands the primary parts, kinds, and functions of neurons.
The Primary Parts of a Neuron
Not all neurons are created the same. Apparently, these specialized nerve cells differ in structure in accordance with their function and location. Nonetheless, every neuron consists of these three primary parts: cell body, axon, and dendrites.
These compositions allow neurons to send and receive information to another neuron, and even to another type of cells.
1. The Cell Body or Soma
The cell body or soma acts as a storehouse which fuels the neuron. In other words, this is the core of the neuron where the signals or information from the dendrites are stored and relayed to another cell body.
Soma is an essential part of the neuron in the maintenance of the neuron’s structure and preservation of energy to ensure the proper performance of the nervous system.
2. The Axon
The axon is a long structure of fiber positioned at the bottom of the cell body. Essentially, this part of the neuron is responsible for the firing and integration of neural signals.
Insulated with myelin – a fatty substance which allows axon to produce signals, axon extends and transmits the signals of the nerve cells away from the soma.
Like the cell body, the axon varies in size and structure.
3. The Dendrites
The dendrites are fibrous extensions from the neuron that branch out from the cell body. This structure of dendrites allows soma to have increased surface area.
The primary function of dendrites includes receiving signals from other nerve cells and relaying them to the cell body.
Naturally, most neurons have numerous dendrites. However, since neurons have different functions and positioning, some of them may have more dendrites – dendritic trees – than the others.
The Three Types of Neurons
As mentioned earlier, not all nerve cells are created the same. Since these specialized neurons vary in function and location, they also appear in different structures and compositions. Thus, neurons are divided into these three categories:
1. The Sensory Neurons
This type of neuron is activated by sensory stimulus from the environment. In other words, these nerve cells transmit signals whenever a person experiences a phenomenon in accordance with his five senses – vision, hearing, smelling, taste, and touch.
Thus, if a person is inflicted with pain, his sensory neurons will send this information to his brain.
2. The Motor Neurons
The motor neurons, on the other hand, controls the human body’s muscle movement. Basically, they transmit signals from the spinal cord to smooth muscles.
Motor neurons are divided into two categories: lower motor the neurons and upper motor neurons. The former are those nerve cells which travel from the spinal cord to the smooth muscles; while the latter travels between the spinal cord and the brain.
3. The Interneurons
Finally, these nerve cells connect the sensory neurons and motor neurons together. Through interneurons, the sensory neurons can transfer signals to the spinal motor.
For instance, if a person is inflicted with pain, his sensory neurons will send this information to the brain. Then, the interneurons will transfer this signal to the motor neurons, which will then transmit it to the spinal cord and to the smooth muscles. Through this process, the person in pain will involuntarily respond to the discomfort experienced accordingly.
The Bottom Line
Neurons are nerve cells that are responsible for the transmission of signals and messages throughout the human body.
Understanding the different parts and types of neurons can provide insights into the interconnectedness between the nervous system and the environment.
Apparently, although we are in the age of modern technology, there are still a lot of things we are yet to understand neurons and our human brain.
I hope that this article on parts and different types of neurons was helpful. If you are interested, make sure to visit the health facts page!