The human body is made up of trillions of cells, the brain alone contains about 100 billion neurons, of various shapes and sizes. The question arises, how is the nerve cell constructed, and how does it differ from other cells in the body?
Human nerve cell device
Like most other cells in the human body, nerve cells have nuclei. But compared to the rest, they are unique, as they have long, filiform branches along which nerve impulses are transmitted.
The cells of the nervous system are similar to others, since they are also surrounded by a cell membrane and have nuclei containing genes, cytoplasm, mitochondria, and other organelles. They participate in such fundamental cellular processes as protein synthesis and energy production.
Neurons and nerve impulses
The nervous system consists of nerves. A nerve is a bundle of nerve cells. A nerve cell transmitting certain information is called a neuron. The data that neurons carry is called nerve impulses. Like electrical impulses, they carry information at an incredible speed. Axons of neurons coated with a special myelin sheath provide fast signal transmission.
This sheath covers the axon like a plastic coating on electrical wires and allows nerve impulses to travel faster. What is a neuron? It has a special shape, which allows you to transmit a signal from one cell to another. A neuron consists of three main parts: the cell body, many dendrites and one axon.
Types of Neurons
Neurons are usually classified based on the role they play in the body. Two main types of neurons are known - sensory and motor. Sensory neurons conduct nerve impulses from the senses and internal organs to the central nervous system (CNS). Motor neurons, on the contrary, carry nerve impulses from the central nervous system to organs, glands and muscles.
The cells of the nervous system are designed in such a way that both types of neurons work together. Sensory neurons carry information about the internal and external environment. This data is used to send signals through motor neurons to tell the body how it should react to the information received.
Synapse
The place where the axon of one neuron corresponds to the dendrites of another is called a synapse. Neurons bind to each other through an electrochemical process. In this case, chemicals called neurotransmitters enter the reaction.
Cell body
The device of a nerve cell suggests the presence of a nucleus and other organelles in the cell body. Dendrites and axons connected to the body of the cell resemble the rays emanating from the sun. Dendrites receive impulses from other nerve cells. Axons transmit nerve impulses to other cells.
A single neuron can have thousands of dendrites, so it can communicate with thousands of other cells. Axon is covered with a myelin sheath - a fat layer that isolates it and allows you to transmit a signal much faster.
Mitochondria
When answering the question of how a nerve cell works, it is important to note the element responsible for the supply of metabolic energy, which can then be easily utilized. In this process, mitochondria play a primary role. These organelles have their own outer and inner membrane.
The main source of energy for the nervous system is glucose. Mitochondria contain enzymes necessary for the conversion of glucose into macroergic compounds, mainly into adenosine triphosphate (ATP) molecules, which can then be transported to other parts of the body that need their energy.
Core
The complex process of protein synthesis begins in the cell nucleus. The nucleus of a neuron contains genetic information that is stored as encoded strings of deoxyribonucleic acid (DNA). Each DNA molecule contains genetic codes for all cells in the body.
It is in the nucleus that the process of constructing protein molecules begins by writing the corresponding part of the DNA code on the complementary molecules of ribonucleic acid (RNA). Released from the nucleus into the intercellular fluid, they start the process of protein synthesis, in which the so-called nucleoli also take part. This is a separate structure within the nucleus responsible for the construction of molecular complexes called ribosomes, which are involved in protein synthesis.
Do you know how a nerve cell works?
Neurons are the most enduring and longest cells in the body! Some of them persist in the human body throughout life. Other cells die, they are replaced by new ones, but many neurons cannot be replaced. With age, they are becoming less. Hence the expression that nerve cells are not restored. However, research data from the late 20th century prove the opposite. In one area of the brain, the hippocampus, new neurons can grow even in adults.
Neurons can be quite large and several meters long (corticospinal and afferent). In 1898, Camillo Golgi, a well-known expert on the nervous system, announced his discovery - a tape-shaped apparatus specializing in neurons in the cerebellum. This device now bears the name of its creator and is known as the "Golgi apparatus."
From the structure of a nerve cell, its definition follows as the main structural and functional element of the nervous system, the study of the simple principles of which can serve as the key to solving many problems. This mainly concerns the autonomic nervous system, which includes hundreds of millions of connected cells.