What can be called the main indicator of the vitality of people? Of course, we are talking about breathing. A person can do without food and water for a while. Without air, vital activity is not possible at all.
General information
What is breathing? This is the link between the environment and people. If air intake is difficult for any reason, then the person’s heart and respiratory organs begin to function in an enhanced mode. This is due to the need to provide sufficient oxygen. The organs of the respiratory system are able to adapt to the conditions of a changing environment.
Interesting Facts
Scientists were able to establish that the air entering the respiratory system of a person forms two flows (conditionally). One of them penetrates the left side of the nose. Examination of the respiratory system shows that the second passes on the right side. Specialists also proved that the arteries of the brain are divided into two streams of air. Therefore, the respiratory process must be correct. This is very important for maintaining normal functioning of people. Consider the structure of the human respiratory system.
Important Features
When we talk about breathing, we are talking about a set of processes that are aimed at ensuring a continuous supply of oxygen to all tissues and organs. At the same time, substances that are formed during the exchange of carbon dioxide are removed from the body. Breathing is a very complex process. It goes through several stages. The stages of entry and exit of air into the body are as follows:
- Ventilation of the lungs. We are talking about gas exchange between atmospheric air and alveoli. This stage is considered external respiration.
- Gas exchange carried out in the lungs. It occurs between the blood and alveolar air.
- Two processes: the delivery of oxygen from the lungs to the tissues, as well as the transport of carbon dioxide from the latter to the former. That is, we are talking about the movement of gases through the bloodstream.
- The next step is the exchange of gases. It involves tissue cells and capillary blood.
- Finally, internal respiration. This refers to the biological oxidation that occurs in the mitochondria of cells.
Main goals
The human respiratory system removes carbon dioxide from the blood. Their task also includes its saturation with oxygen. If we list the functions of the respiratory system, then this is the most important.
Additional purpose
There are other functions of the human respiratory system, among them we can distinguish the following:
- Taking part in the processes of thermoregulation. The fact is that the temperature of the inhaled air has an effect on a similar parameter of the human body. During exhalation, the body gives off heat to the external environment. At the same time, it cools, if possible.
- Taking part in excretory processes. During exhalation, water vapor is eliminated from the body (except for carbon dioxide) along with air. This also applies to some other substances. For example, ethyl alcohol during intoxication.
- Taking part in immune responses. Thanks to this function of the human respiratory system, it becomes possible to render harmless some pathologically dangerous elements. These include, in particular, pathogenic viruses, bacteria and other microorganisms. Certain lung cells are endowed with this ability. In this regard, they can be attributed to the elements of the immune system.
Specific tasks
There are very narrow functions of the respiratory system. In particular, specific tasks are performed by the bronchi, trachea, larynx, and nasopharynx. Among such narrowly focused functions, the following can be distinguished:
- Cooling and warming the incoming air. This task is carried out in accordance with the ambient temperature.
- Humidification of the air (inhaled), which prevents drying of the lungs.
- Purification of incoming air. In particular, this applies to foreign particles. For example, to dust entering with air.
The structure of the human respiratory system
All elements are connected by special channels. Air enters and exits through them. Also included in this system are the lungs - the organs where gas exchange takes place. The device of the whole complex and the principle of its operation are quite complex. Consider the human respiratory system (pictures below) in more detail.
Nasal cavity information
The airways begin with her. The nasal cavity is separated from the oral cavity. The front is hard sky, and the back is soft. The nasal cavity has a cartilaginous and bone skeleton. It is divided into left and right parts due to a solid partition. Three nasal concha are also present . Thanks to them, the cavity is divided into passages:
- Lower.
- Middle.
- Upper.
The exhaled and inhaled air passes through them.
Features of the mucosa
She has a number of devices that are designed to handle inhaled air. First of all, it is covered by the ciliated epithelium. His cilia formed a continuous carpet. Due to the fact that the cilia flicker, the dust is quite easily eliminated from the nasal cavity. The hairs that are located at the outer edge of the holes also contribute to the retention of foreign elements. The mucous membrane contains special glands. Their secret envelops the dust and helps to eliminate it. In addition, air humidification occurs.
The mucus that is in the nasal cavity has bactericidal properties. It contains lysozyme. This substance reduces the ability of bacteria to reproduce. It also kills them. In the mucous membrane there are many venous vessels. Under various conditions, they can swell. If they are damaged, then nosebleeds begin. The purpose of these formations is to heat the air stream passing through the nose. White blood cells leave the blood vessels and appear on the surface of the mucosa. They also perform protective functions. In the process of phagocytosis, leukocytes die. Thus, the mucus that is secreted from the nose contains many dead “protectors”. Further, the air passes into the nasopharynx, and from there to other organs of the respiratory system.
Larynx
It is located in the anterior laryngeal part of the pharynx. This is the level of the 4-6th cervical vertebrae. Larynx is formed by cartilage. The latter are divided into paired (wedge-shaped, horn-shaped, aryteniform) and unpaired (cricoid, thyroid). In this case, the epiglottis is attached to the upper edge of the last cartilage. During swallowing, he closes the entrance to the larynx. Thus, it prevents food from entering it.
Two vocal cords go from the thyroid to the arytenoid cartilage. The glottis is the space that forms between them.
General information about the trachea
She is a continuation of the larynx. It is divided into two bronchi: left and right. Bifurcation is the place where the trachea branches. The following length is characteristic of it: 9-12 centimeters. On average, the transverse diameter reaches eighteen millimeters.
A trachea can include up to twenty incomplete cartilage rings. They are connected using fibrous ligaments. Thanks to the cartilaginous half rings, the airways become elastic. In addition, they become falling, therefore, easily passable for air.
The membranous posterior wall of the trachea is flattened. It contains smooth muscle tissue (bundles that run longitudinally and transversely). This ensures the active movement of the trachea during coughing, breathing and so on. As for the mucous membrane, it is covered by the ciliated epithelium. In this case, the exception is the part of the epiglottis and the vocal cords. She also has mucous glands and lymphoid tissue.
Bronchi
This is a paired element. Two bronchi, into which the trachea is divided, enter the left and right lungs. There, they tree-like branch into smaller elements that are included in the pulmonary lobules. So, bronchioles form. We are talking about even smaller respiratory branches. The diameter of the respiratory bronchioles may be 0.5 mm. They, in turn, form alveolar passages. The latter end with the corresponding bags.
What are alveoli? These are protrusions, having the form of bubbles, which are located on the walls of the corresponding sacs and passages. Their diameter reaches 0.3 mm, and the number can reach up to 400 million. This provides the opportunity to create a large respiratory surface. This factor significantly affects lung volume. The latter can be increased.
The most important human respiratory system
They are considered lungs. Serious illnesses associated with them can be life threatening. Lungs (photos are presented in the article) are located in the chest cavity, which is hermetically closed. Its posterior wall is formed by the corresponding spine and ribs, which are attached movably. Between them are internal and external muscles.
The chest cavity is separated from the abdominal cavity from below. This involves the abdominal obstruction, or diaphragm. Anatomy of the lungs is not simple. A person has two. The right lung includes three lobes. At the same time, the left consists of two. The apex of the lungs is their narrowed upper part, and the expanded lower is considered the base. The gates are different. They are represented by recesses on the inner surface of the lungs. Blood vessels, bronchi, nerves, and also lymph vessels pass through them. The root is represented by a combination of the above formations.
Lungs (the photo illustrates their location), or rather their tissue, consist of small structures. They are called slices. We are talking about small areas having a pyramidal shape. The bronchi, which are included in the corresponding lobule, are divided into respiratory bronchioles. The alveolar passage is at the end of each of them. This whole system is a functional unit of the lungs. It is called acinus.
The lungs are covered with pleura. This is a shell consisting of two elements. We are talking about the external (parietal) and internal (visceral) lobes (lung scheme is attached below). The latter covers them and at the same time is the outer shell. He makes the transition to the outer pleura on the root and represents the inner shell of the walls of the chest cavity. This leads to the formation of a geometrically enclosed minute capillary space. It is a pleural cavity. It contains a small amount of appropriate fluid. She soaks the pleura. Thanks to this, their sliding between each other is facilitated. Air changes in the lungs occur for many reasons. One of the main is the change in the size of the pleural and chest cavities. This is the anatomy of the lungs.
Features of the mechanism of entry and exit of air
As mentioned earlier, an exchange occurs between the gas in the alveoli and the atmosphere. This is due to the rhythmic alternation of inspirations and exhalations. The lungs do not have muscle tissue. For this reason, their intensive reduction is impossible. In this case, the most active role is given to the respiratory muscles. With their paralysis, it is not possible to take a breath. In this case, the respiratory system is not affected.
Inspiration is an act of inspiration. This is an active process, during which an increase in the chest is ensured. Expiration is an act of expiration. This process is passive. It occurs due to the fact that the chest cavity is reduced.
The respiratory cycle is represented by the phases of inspiration and subsequent exhalation. In the process of air entry, the diaphragm and the external oblique muscles participate. With their contraction, the ribs begin to rise. At the same time, there is an increase in the chest cavity. The diaphragm contracts. Moreover, it occupies a flatter position.
As for the incompressible organs of the abdominal cavity, during the process under consideration they are pushed to the sides and down. With a calm breath, the dome of the diaphragm drops by about one and a half centimeters. Thus, there is an increase in the vertical size of the chest cavity. In the case of very deep breathing, auxiliary muscles take part in the act of inspiration, among which the following stand out:
- Diamond-shaped (which raise the shoulder blade).
- Trapezoidal.
- Small and large pectoral.
- Front gear.
The wall of the chest cavity and lungs is covered by the serous membrane. The pleural cavity is represented by a narrow gap between the leaves. It contains serous fluid. Lungs all the time in a stretched state. This is due to the fact that the pressure in the pleural cavity is negative. It is about elastic traction. The fact is that lung volume is constantly striving to decrease. At the end of a quiet exhalation, almost every respiratory muscle relaxes. In this case, the pressure in the pleural cavity is lower than atmospheric. In different people, the main role in the act of inspiration is played by the diaphragm or intercostal muscles. In accordance with this, we can talk about different types of breathing:
- Rib.
- Aperture.
- Abdominal.
- Breast.
It is now known that in women, the latter type of respiration predominates. In men, in most cases, abdominal is observed. During calm breathing, exhalation occurs due to elastic energy. It accumulates during the previous breath. When the muscles relax, the ribs can passively return to their original position. If the contractions of the diaphragm decrease, then it will take its former domed position. This is due to the fact that the organs of the abdominal cavity act on it. Thus, the pressure in it decreases.
All of the above processes lead to compression of the lungs. Air comes out of them (passively). Enhanced expiration is an active process. It involves the internal intercostal muscles. At the same time, their fibers go in the opposite direction, if we compare with the external ones. They contract and the ribs go down. There is also a decrease in the chest cavity.