The respiratory system consists of the following organs. What about the respiratory system

We breathe air from the atmosphere; the body exchanges oxygen and carbon dioxide, after which the air is exhaled. During the day, this process is repeated many thousands of times; it is vital for every single cell, tissue, organ and organ system.

The respiratory system can be divided into two main sections: the upper and lower respiratory tract.

Upper respiratory tract:

sinuses
Pharynx
Larynx

Lower respiratory tract:

Trachea
Bronchi
Lungs

The ribcage protects the lower airways:

12 pairs of ribs forming a cage-like structure
12 thoracic vertebrae to which the ribs are attached
The sternum to which the ribs are attached in front

The structure of the upper respiratory tract

Nose

The nose is the main passage through which air enters and exits the body.

The nose is made up of:

Nasal bone that forms the back of the nose.
The nasal concha, from which the lateral wings of the nose are formed.
The tip of the nose is formed by flexible septal cartilage.

The nostrils are two separate openings leading into the nasal cavity, separated by a thin cartilaginous wall - the septum. The nasal cavity is lined with a ciliated mucosa composed of cells that have cilia that act like a filter. The cuboidal cells produce mucus, which catches any foreign particles that enter the nose.

sinuses

Sinuses are air-filled cavities in the frontal, ethmoid, sphenoid bones and mandible that open into the nasal cavity. The sinuses are lined with a mucous membrane like the nasal cavity. Mucus retention in the sinuses can cause headaches.

Pharynx

The nasal cavity passes into the pharynx (the back of the throat), which is also covered with a mucous membrane. The pharynx is composed of muscular and fibrous tissue and can be divided into three sections:

The nasopharynx, or nasal part of the pharynx, provides airflow when we breathe through the nose. It is connected to both ears by channels - the Eustachian (auditory) tubes - containing mucus. Through the auditory tubes, throat infections can easily spread to the ears. Adenoids are located in this part of the larynx. They are composed of lymphatic tissue and perform an immune function by filtering out harmful air particles.
The oropharynx, or oral part of the pharynx, is the path for the passage of air inhaled by the mouth and food. It contains tonsils, which, like adenoids, have a protective function.
The hypopharynx serves as a passage for food before it enters the esophagus, which is the first part of the digestive tract and leads to the stomach.

Larynx

The pharynx passes into the larynx (upper throat), through which air enters further. Here he continues to purify himself. The larynx contains cartilages that form the vocal folds. The cartilage also forms a lid-like epiglottis that hangs over the entrance to the larynx. The epiglottis prevents food from entering the respiratory tract when swallowed.

The structure of the lower respiratory tract

Trachea

The trachea begins after the larynx and extends down to the chest. Here, air filtration by the mucous membrane continues. The trachea in front is formed by C-shaped hyaline cartilages, connected behind in circles by visceral muscles and connective tissue. These semi-solid formations do not allow the trachea to contract and airflow is not blocked. The trachea descends into the chest by about 12 cm and there it diverges into two sections - the right and left bronchi.

Bronchi

Bronchi - paths similar in structure to the trachea. Through them, air enters the right and left lungs. The left bronchus is narrower and shorter than the right one and is divided into two parts at the entrance to the two lobes of the left lung. The right bronchus is divided into three parts, since the right lung has three lobes. The mucous membrane of the bronchi continues to purify the air passing through them.

Lungs

The lungs are soft spongy oval structures located in the chest on either side of the heart. The lungs are connected to the bronchi, which diverge before entering the lobes of the lungs.

In the lobes of the lungs, the bronchi branch further, forming small tubes - bronchioles. The bronchioles have lost their cartilaginous structure and are made up of only smooth tissue, making them soft. The bronchioles end in alveoli, small air sacs that are supplied with blood through a network of small capillaries. In the blood of the alveoli, a vital process of exchange of oxygen and carbon dioxide takes place.

Outside, the lungs are covered with a protective sheath called the pleura, which has two layers:

Smooth inner layer attached to the lungs.
Parietal outer layer connected to the ribs and the diaphragm.

The smooth and parietal layers of the pleura are separated by the pleural cavity, which contains a liquid lubricant that provides movement between the two layers and breathing.

Functions of the respiratory system

Respiration is the process of exchanging oxygen and carbon dioxide. Oxygen is inhaled, transported by blood cells so that nutrients from the digestive system can be oxidized, i.e. broken down, adenosine triphosphate was produced in the muscles and a certain amount of energy was released. All body cells need a constant supply of oxygen to keep them alive. Carbon dioxide is formed during the absorption of oxygen. This substance must be removed from the cells in the blood, which transports it to the lungs, and it is exhaled. We can live without food for several weeks, without water for several days, and without oxygen for only a few minutes!

The process of respiration includes five actions: inhalation and exhalation, external respiration, transportation, internal respiration and cellular respiration.

Breath

Air enters the body through the nose or mouth.

Breathing through the nose is more efficient because:

The air is filtered by cilia, cleared of foreign particles. They are thrown back when we sneeze or blow our nose, or they get into the hypopharynx and are swallowed.
Passing through the nose, the air is heated.
The air is moistened with water from mucus.
Sensory nerves sense the smell and report it to the brain.

Breathing can be defined as the movement of air into and out of the lungs as a result of inhalation and exhalation.

Inhale:

The diaphragm contracts, pushing the abdominal cavity down.
The intercostal muscles contract.
The ribs rise and expand.
The chest cavity is enlarged.
The pressure in the lungs decreases.
The air pressure increases.
Air fills the lungs.
The lungs expand as they fill with air.

Exhalation:

The diaphragm relaxes and returns to its domed shape.
The intercostal muscles relax.
The ribs return to their original position.
The chest cavity returns to normal.
The pressure in the lungs increases.
The air pressure is decreasing.
Air can come out of the lungs.
The elastic recoil of the lung helps expel air.
Contraction of the abdominal muscles increases expiration, lifting the abdominal organs.

After exhalation, there is a short pause before a new breath, when the pressure in the lungs is the same as the air pressure outside the body. This state is called equilibrium.

Breathing is controlled by the nervous system and occurs without conscious effort. The respiratory rate varies depending on the state of the body. For example, if we need to run to catch a bus, it increases to provide the muscles with enough oxygen to complete the task. After we have boarded the bus, the respiratory rate decreases as the oxygen demand of the muscles decreases.

External respiration

The exchange of oxygen from the air and carbon dioxide occurs in the blood in the alveoli of the lungs. This exchange of gases is possible due to the difference in pressure and concentration in the alveoli and capillaries.

The air entering the alveoli has more pressure than the blood in the surrounding capillaries. Because of this, oxygen can easily pass into the blood, increasing the pressure in it. When the pressure equalizes, this process, called diffusion, stops.
Carbon dioxide in the blood, brought from the cells, has a greater pressure than the air in the alveoli, in which its concentration is lower. As a result, carbon dioxide contained in the blood can easily penetrate from the capillaries into the alveoli, raising the pressure in them.

Transportation

Transportation of oxygen and carbon dioxide is carried out through the pulmonary circulation:

After gas exchange in the alveoli, the blood carries oxygen to the heart through the veins of the pulmonary circulation, from where it is distributed throughout the body and consumed by cells that emit carbon dioxide.
After that, the blood carries carbon dioxide to the heart, from where it enters the lungs through the arteries of the pulmonary circulation and is removed from the body with exhaled air.

internal breathing

Transportation ensures the supply of oxygen-enriched blood to cells in which gas exchange occurs by diffusion:

The pressure of oxygen in the brought blood is higher than in the cells, so oxygen easily penetrates into them.
The pressure in the blood coming from the cells is less, which allows carbon dioxide to penetrate into it.

The oxygen is replaced by carbon dioxide, and the whole cycle begins anew.

Cellular respiration

Cellular respiration is the uptake of oxygen by cells and the production of carbon dioxide. Cells use oxygen to produce energy. During this process, carbon dioxide is released.

It is important to understand that the process of breathing is a defining process for each individual cell, and the frequency and depth of breathing must correspond to the needs of the body. Although the process of breathing is controlled by the autonomic nervous system, some factors such as stress and poor posture can affect the respiratory system, reducing the efficiency of breathing. This, in turn, affects the work of cells, tissues, organs and systems of the body.

During the procedures, the therapist must monitor both his own breathing and the breathing of the patient. The therapist's breathing speeds up with increasing physical activity, and the client's breathing calms down as he relaxes.

Possible violations

Possible disorders of the respiratory system from A to Z:

Enlarged adenoids - can block the entrance to the auditory tube and / or the passage of air from the nose to the throat.
ASTHMA - Difficulty breathing due to narrow airways. It can be caused by external factors - acquired bronchial asthma, or internal - hereditary bronchial asthma.
BRONCHITIS - inflammation of the lining of the bronchi.
HYPERVENTILATION - rapid, deep breathing, usually associated with stress.
INFECTIOUS MONONUCLEOSIS is a viral infection that most affects the age group from 15 to 22 years. Symptoms are persistent sore throat and/or tonsillitis.
CRUP is a childhood viral infection. Symptoms are fever and severe dry cough.
Laryngitis - inflammation of the larynx causing hoarseness and/or loss of voice. There are two types: acute, which develops quickly and passes quickly, and chronic - periodically recurring.
Nasal polyp - a harmless growth of the mucous membrane in the nasal cavity, containing fluid and obstructing the passage of air.
ARI is a contagious viral infection, the symptoms of which are sore throat and runny nose. Usually lasts 2-7 days, full recovery can take up to 3 weeks.
PLEURITIS is an inflammation of the pleura surrounding the lungs, usually occurring as a complication of other diseases.
PNEUMONIA - inflammation of the lungs as a result of a bacterial or viral infection, manifested as chest pain, dry cough, fever, etc. Bacterial pneumonia takes longer to heal.
PNEUMOTHORAX - a collapsed lung (possibly as a result of a lung rupture).
Pollinosis is a disease caused by an allergic reaction to pollen. Affects the nose, eyes, sinuses: pollen irritates these areas, causing a runny nose, inflammation of the eyes and excess mucus. The respiratory tract can also be affected, then breathing becomes difficult, with whistles.
LUNG CANCER is a life-threatening malignant lung tumor.
Cleft palate - deformity of the palate. Often occurs simultaneously with cleft lip.
RINITIS - inflammation of the mucous membrane of the nasal cavity, which causes a runny nose. The nose may be blocked.
SINUSITIS - Inflammation of the lining of the sinuses causing a blockage. It can be very painful and cause inflammation.
STRESS - a state that causes the autonomous system to increase the release of adrenaline. This causes rapid breathing.
TONSILLITIS - inflammation of the tonsils, causing sore throat. More often occurs in children.
TUBERCULOSIS is an infectious disease that causes the formation of nodules in tissues, most often in the lungs. Vaccination is possible. Pharyngitis - inflammation of the pharynx, manifested as a sore throat. May be acute or chronic. Acute pharyngitis is very common, disappearing in about a week. Chronic pharyngitis lasts longer, is typical for smokers. Emphysema - inflammation of the alveoli of the lungs, causing a slowdown in the flow of blood through the lungs. It usually accompanies bronchitis and/or occurs in old age. The respiratory system plays a vital role in the body.

Knowledge

You should monitor the correct breathing, otherwise it can cause a number of problems.

These include: muscle cramps, headaches, depression, anxiety, chest pain, fatigue, etc. To avoid these problems, you need to know how to breathe correctly.

There are the following types of breathing:

Lateral costal - normal breathing, in which the lungs receive enough oxygen for daily needs. This type of breathing is associated with the aerobic energy system, filling the upper two lobes of the lungs with air.
Apical - shallow and rapid breathing, which is used to get the maximum amount of oxygen to the muscles. Such cases include sports, childbirth, stress, fear, etc. This type of respiration is associated with the anaerobic energy system and leads to oxygen debt and muscle fatigue if energy requirements exceed oxygen intake. Air enters only the upper lobes of the lungs.
Diaphragmatic - deep breathing associated with relaxation, which makes up for any oxygen debt received as a result of apical breathing, In which the lungs can completely fill with air.

Proper breathing can be learned. Practices like yoga and tai chi place a lot of emphasis on breathing technique.

As far as possible, breathing techniques should accompany procedures and therapy, as they are beneficial for both the therapist and the patient and allow the mind to be cleared and the body to be energized.

Begin the treatment with a deep breathing exercise to release the patient's stress and tension and prepare him for therapy.
Ending the procedure with a breathing exercise will allow the patient to see the relationship between breathing and stress levels.

Breathing is underestimated, taken for granted. Nevertheless, special care must be taken to ensure that the respiratory system can perform its functions freely and efficiently and does not experience stress and discomfort, which I can not avoid.

Respiratory system.

Functions of the respiratory system:

1. Provides body tissues with oxygen and removes carbon dioxide from them;

3. participates in the sense of smell;

4. is involved in the production of hormones; ss

5. participates in metabolism;

6. participates in immunological protection.

In the airways, the air is warmed or cooled, cleaned, moistened, and the perception of olfactory, thermal and mechanical irritations also occurs. The respiratory system begins with the nasal cavity.

The nostrils are the entrances to the nasal cavity. The anterior inferior wall separates the nasal cavity from the oral cavity and consists of the soft and hard palate. The back wall of the nose is the nasopharyngeal opening (choanae) which passes into the nasopharynx. The nasal plate consists of the anterior ethmoid bone and the vomer. From the nasal septum to the side on different sides are curved bone plates - nasal conchas. The nasolacrimal canal opens into the lower nasal passage.

The mucous membrane is lined with ciliated epithelium and contains a significant amount of glands that secrete mucus. There are also many vessels that warm the cold air, and nerves that perform an olfactory function, therefore it is considered an organ of smell. Through the choanae, air enters the pharynx, and then into the larynx.

Larynx (larynx)- located in the front of the neck at the level of IV-VII cervical vertebrae; on the surface of the neck forms a small (in women) and strongly protruding forward (in men) elevation - a protrusion of the larynx (Adam's apple, Adam's apple - prominentico lyngeria). In front, the larynx is suspended from the hyoid bone, at the bottom it connects to the trachea. In front of the larynx lie the muscles of the neck, on the side - the neurovascular bundles. Consists of cartilage. They are divided into:

1. unpaired (cricoid, thyroid, epiglottis);

2. paired (arytenoid, corniculate, wedge-shaped).

Cartilages of the larynx.

main cartilage- this is the cricoid cartilage, which connects below with ligaments to the first cartilaginous ring.

The basis of the larynx is hyaline cricoid cartilage, which connects to the first cartilage of the trachea with a ligament. It has an arc and a quadrangular plate; the cartilage arc is directed forward, the plate is backward. On the arc of the cricoid cartilage is hyaline unpaired, the largest cartilage of the larynx - thyroid. arytenoid cartilage paired, hyaline, similar to a quadrangular pyramid. corniculate And sphenoid cartilage are located in the thickness of the arytenoid ligament.

The cartilages of the larynx are interconnected by means of joints and ligaments. Muscles of the larynx. All the muscles of the larynx are divided into three groups: dilators that narrow the glottis and change the tension of the vocal cords. 1. The muscle that expands the glottis - posterior cricoarytenoid(pair muscle);

The larynx has shells:

1.mucous – covered with ciliated epithelium, except for the vocal cords.

2. fibrocartilaginous - - consists of hyaline and elastic cartilage.

3. connective tissue (adventitia).

In children, the size of the larynx is smaller than in adults; the vocal cords are shorter, the timbre of the voice is higher. The size of the larynx can change during puberty, which leads to a change in voice.

Trachea- this is a tube 10-15 cm long, has 2 parts: cervical and chest. The esophagus passes behind, the thyroid gland, thymus gland, aortic arch and its branches pass in front. At the level of the lower edge of the VI cervical vertebra, and ends at the level of the upper edge of the V thoracic vertebra. It is divided into 2 bronchi, which depart into the right and left lungs. This place is called a bifurcation.

Right - length 3 cm., consists of 6-8 cartilages. Shorter and wider, departs from the trachea with an obtuse angle.

Left - length 4-5 cm., consists of 9-12 cartilages. Long and narrow, runs under the aortic arch.

The trachea and bronchi consist of 16-20 hyaline cartilage semirings. The semirings are connected to each other by ring ligaments. From the inside, the trachea and bronchi are lined with a mucous membrane, then a submucosa, and behind it is a cartilaginous tissue. The mucous membrane has no folds, it is lined with multi-row plasma ciliated epithelium and also has a large number of goblet cells.

Lungs (pulmones)- These are the main organs of the respiratory apparatus, they occupy almost the entire cavity of the chest. They change shape and size depending on the phase of respiration. It has the shape of a truncated cone. The apex of the lung faces over the clavicular fossa. Below the lungs have a concave base. They are adjacent to the diaphragm.

There are three surfaces in the lung: convex, ribbed adjacent to the inner surface of the wall of the chest cavity; diaphragmatic- adjacent to the diaphragm; medial (mediastinal) directed towards the mediastinum.

Each lung is divided into lobes by furrows: the right - into 3 (upper, middle, lower), the left into 2 (upper and lower).

Each lung consists of branched bronchi, which form the bronchial tree and the system of pulmonary vesicles. Bronchus with a diameter of 1 mm is called lobular. Each alveolar passage ends with two alveolar sacs. The walls of the alveolar sacs are composed of their pulmonary alveoli. The diameter of the alveolar passage and the alveolar sac is 0.2 - 0.6 mm, the alveoli - 0.25-0.30 mm.

Respiratory bronchioles, as well as alveolar passages, alveolar sacs and alveoli of the lung form alveolar tree (pulmonary acinus), which is the structural and functional unit of the lung. The number of pulmonary acini in one lung is 15,000; the number of alveoli is on average 300-350 million, and the area of the respiratory surface of all alveoli is about 80 m 2.

Pleura- a thin smooth serous membrane that envelops each lung.

Distinguish visceral pleura, which fuses tightly with lung tissue and enters the gaps between the lobes of the lung, and parietal, which lines the wall of the chest cavity.

The parietal pleura consists of the costal, mediastinal, and diaphragmatic pleura.

Between the parietal and visceral pleura, a slit-like closed space is formed - pleural cavity. It contains a small amount of serous fluid.

Mediastinum (mediastinum) - is a complex of organs located between the right and left pleural cavities. The mediastinum is bounded anteriorly by the sternum, posteriorly by the thoracic spine, laterally by the right and left mediastinal pleura. Above, the mediastinum continues to the upper aperture of the chest, below - to the diaphragm. There are two sections of the mediastinum: superior and inferior.

In one day, an adult person inhales and exhales tens of thousands of times. If a person cannot breathe, then he has only seconds.

The importance of this system for a person is difficult to overestimate. You need to think about how the human respiratory system works, what its structure and functions are, before health problems can appear.

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The structure of the human respiratory system

The pulmonary system can be considered as one of the most essential in the human body. It includes functions aimed at the assimilation of oxygen from the air and the removal of carbon dioxide. Normal work of breathing is especially important for children.

The anatomy of the respiratory organs provides that they can be divided into two groups:

airways;
lungs.

upper respiratory tract

When air enters the body, it passes through the mouth or nose. Moves further through the pharynx, entering the trachea.

The upper respiratory tract includes the paranasal sinuses, as well as the larynx.

The nasal cavity is divided into several sections: lower, middle, upper and general.

Inside, this cavity is covered with ciliated epithelium, which warms up the incoming air and purifies it. Here is a special mucus that has protective properties that help fight infection.

The larynx is a cartilaginous formation that is located between the pharynx and the trachea.

lower respiratory tract

When inhalation occurs, air moves inward and enters the lungs. At the same time, from the pharynx at the beginning of its journey, it ends up in the trachea, bronchi and lungs. Physiology refers them to the lower respiratory tract.

In the structure of the trachea, it is customary to distinguish the cervical and thoracic parts. It is divided into two parts. It, like other respiratory organs, is covered with ciliated epithelium.

In the lungs, departments are distinguished: the top and the base. This organ has three surfaces:

diaphragmatic;
mediastinal;
costal.

The lung cavity is protected, in short, by the thorax from the sides and by the diaphragm from below the abdominal cavity.

Inhalation and exhalation are controlled by:

diaphragm;
intercostal respiratory muscles;
intercartilaginous internal muscles.

Functions of the respiratory system

The most important function of the respiratory system is to: supply the body with oxygen in order to adequately ensure its vital activity, as well as remove carbon dioxide and other decay products from the human body by performing gas exchange.

The respiratory system also performs a number of other functions:

Creation of air flow to ensure the formation of voice.
Obtaining air for odor recognition.
The role of respiration also consists in the fact that it provides ventilation to maintain the optimal temperature of the body;
These organs are also involved in the process of blood circulation.
A protective function is carried out against the threat of pathogens entering along with the inhaled air, including when a deep breath occurs.
To a small extent, external respiration contributes to the removal of waste substances from the body in the form of water vapor. In particular, dust, urea and ammonia can be removed in this way.
The pulmonary system performs the deposition of blood.

In the latter case, the lungs, thanks to their structure, are able to concentrate a certain volume of blood, giving it to the body when the general plan requires it.

The mechanism of human respiration

The breathing process consists of three processes. The following table explains this.

Oxygen can enter the body through the nose or mouth. Then it passes through the pharynx, larynx and enters the lungs.

Oxygen enters the lungs as one of the components of air. Their branched structure contributes to the fact that O2 gas dissolves in the blood through the alveoli and capillaries, forming unstable chemical compounds with hemoglobin. Thus, in a chemically bound form, oxygen moves through the circulatory system throughout the body.

The regulation scheme provides that O2 gas gradually enters the cells, being released from the connection with hemoglobin. At the same time, the carbon dioxide exhausted by the body takes its place in transport molecules and is gradually transferred to the lungs, where it is excreted from the body during exhalation.

Air enters the lungs because their volume periodically increases and decreases. The pleura is attached to the diaphragm. Therefore, with the expansion of the latter, the volume of the lungs increases. Taking in air, internal breathing is carried out. If the diaphragm contracts, the pleura pushes the waste carbon dioxide out.

It is worth noting: within one minute a person needs 300 ml of oxygen. During the same time, there is a need to remove 200 ml of carbon dioxide from the body. However, these figures are valid only in a situation where a person does not experience strong physical exertion. If there is a maximum breath, they will increase many times over.

Various types of breathing can take place:

At chest breathing inhalation and exhalation are carried out due to the efforts of the intercostal muscles. At the same time, during inhalation, the chest expands and also rises slightly. Exhalation is performed in the opposite way: the cell is compressed, at the same time slightly lowering.
Abdominal type of breathing looks different. The process of inhalation is carried out due to the expansion of the abdominal muscles with a slight rise in the diaphragm. As you exhale, these muscles contract.

The first of them is most often used by women, the second - by men. In some people, both the intercostal and abdominal muscles can be used in the process of breathing.

Diseases of the human respiratory system

Such diseases usually fall into one of the following categories:

In some cases, an infection can be the cause. The cause can be microbes, viruses, bacteria, which, once in the body, have a pathogenic effect.
Some people have allergic reactions, which are expressed in various breathing problems. There can be many reasons for such disorders, depending on the type of allergy that a person has.
Autoimmune diseases are very dangerous to health. In this case, the body perceives its own cells as pathogens and begins to fight them. In some cases, the result can be a disease of the respiratory system.
Another group of diseases are those that are hereditary. In this case, we are talking about the fact that at the gene level there is a predisposition to certain diseases. However, by paying sufficient attention to this issue, in most cases, the disease can be prevented.

To control the presence of the disease, you need to know the signs by which you can determine its presence:

cough;
dyspnea;
pain in the lungs;
feeling of suffocation;
hemoptysis.

Cough is a reaction to mucus accumulated in the bronchi and lungs. In different situations, it can vary in nature: with laryngitis it is dry, with pneumonia it is wet. In the case of ARVI diseases, coughing can periodically change its character.

Sometimes when coughing, the patient experiences pain, which can occur either constantly or when the body is in a certain position.

Shortness of breath can manifest itself in different ways. Subjective intensifies at times when a person is under stress. Objective is expressed in a change in the rhythm and strength of breathing.

Importance of the respiratory system

The ability of people to talk is largely based on the correct work of breathing.

This system also plays a role in the body's thermoregulation. Depending on the specific situation, this makes it possible to raise or lower body temperature to the desired degree.

With respiration, in addition to carbon dioxide, some other waste products of the human body are also removed.

Thus, a person is given the opportunity to distinguish different smells by inhaling air through the nose.

Thanks to this system of the body, a person's gas exchange with the environment, the supply of organs and tissues with oxygen and the removal of exhaust carbon dioxide from the human body are carried out.

Respiration is a complex and continuous biological process, as a result of which the body consumes free electrons and oxygen from the external environment, and releases carbon dioxide and water saturated with hydrogen ions.

The human respiratory system is a set of organs that provide the function of external human respiration (gas exchange between the inhaled atmospheric air and the blood circulating in the pulmonary circulation).

Gas exchange is carried out in the alveoli of the lungs, and is normally aimed at capturing oxygen from the inhaled air and releasing carbon dioxide formed in the body into the external environment.

An adult, being at rest, takes an average of 15-17 breaths per minute, and a newborn child takes 1 breath per second.

Ventilation of the alveoli is carried out by alternating inhalation and exhalation. When you inhale, atmospheric air enters the alveoli, and when you exhale, air saturated with carbon dioxide is removed from the alveoli.

A normal calm breath is associated with the activity of the muscles of the diaphragm and the external intercostal muscles. When you inhale, the diaphragm lowers, the ribs rise, the distance between them increases. The usual calm exhalation occurs to a large extent passively, while the internal intercostal muscles and some abdominal muscles are actively working. When exhaling, the diaphragm rises, the ribs move down, the distance between them decreases.

Types of breathing

The respiratory system performs only the first part of gas exchange. The rest is performed by the circulatory system. There is a deep relationship between the respiratory and circulatory systems.

There are pulmonary respiration, which provides gas exchange between air and blood, and tissue respiration, which performs gas exchange between blood and tissue cells. It is carried out by the circulatory system, since the blood delivers oxygen to the organs and carries away decay products and carbon dioxide from them.

Lung breathing. The exchange of gases in the lungs occurs due to diffusion. The blood that has come from the heart into the capillaries braiding the pulmonary alveoli contains a lot of carbon dioxide, there is little of it in the air of the pulmonary alveoli, so it leaves the blood vessels and passes into the alveoli.

Oxygen enters the blood also through diffusion. But in order for this gas exchange to go on continuously, it is necessary that the composition of gases in the pulmonary alveoli be constant. This constancy is maintained by pulmonary respiration: excess carbon dioxide is removed outside, and oxygen absorbed by the blood is replaced by oxygen from a fresh portion of the outside air.

tissue respiration. Tissue respiration occurs in the capillaries, where the blood gives off oxygen and receives carbon dioxide. There is little oxygen in the tissues, therefore, the breakdown of oxyhemoglobin into hemoglobin and oxygen occurs. Oxygen passes into the tissue fluid and there it is used by cells for the biological oxidation of organic substances. The energy released in this process is used for the vital processes of cells and tissues.

With insufficient oxygen supply to the tissues: the function of the tissue is impaired, because the decay and oxidation of organic substances stops, energy ceases to be released, and cells deprived of energy supply die.

The more oxygen is consumed in the tissues, the more oxygen is required from the air to compensate for the costs. That is why during physical work, both cardiac activity and pulmonary respiration are simultaneously enhanced.

Breath types

According to the method of expansion of the chest, two types of breathing are distinguished:

chest type of breathing(expansion of the chest is made by raising the ribs), more often observed in women;
abdominal type of breathing(expansion of the chest is produced by flattening the diaphragm,) is more common in men.

Breathing happens:

deep and superficial;
frequent and rare.

Special types of respiratory movements are observed with hiccups and laughter. With frequent and shallow breathing, the excitability of the nerve centers increases, and with deep breathing, on the contrary, it decreases.

The system and structure of the respiratory system

The respiratory system includes:

upper respiratory tract: nasal cavity, nasopharynx, pharynx;
lower respiratory tract: larynx, trachea, main bronchi and lungs covered with pulmonary pleura.

The symbolic transition of the upper respiratory tract to the lower is carried out at the intersection of the digestive and respiratory systems in the upper part of the larynx. The respiratory tract provides connections between the environment and the main organs of the respiratory system - the lungs.

The lungs are located in the chest cavity, surrounded by the bones and muscles of the chest. The lungs are in hermetically sealed cavities, the walls of which are lined with parietal pleura. Between the parietal and pulmonary pleura is a slit-like pleural cavity. The pressure in it is lower than in the lungs, and therefore the lungs are always pressed against the walls of the chest cavity and take its shape.

Entering the lungs, the main bronchi branch, forming a bronchial tree, at the ends of which there are pulmonary vesicles, alveoli. Through the bronchial tree, air reaches the alveoli, where gas exchange occurs between the atmospheric air that has reached the pulmonary alveoli (lung parenchyma) and the blood flowing through the pulmonary capillaries, which ensure the supply of oxygen to the body and the removal of gaseous waste products from it, including carbon dioxide. gas.

Breathing process

Inhalation and exhalation is carried out by changing the size of the chest with the help of the respiratory muscles. During one breath (in a calm state), 400-500 ml of air enters the lungs. This volume of air is called the tidal volume (TO). The same amount of air enters the atmosphere from the lungs during a quiet exhalation.

The maximum deep breath is about 2,000 ml of air. After maximum exhalation, about 1200 ml of air remains in the lungs, called the residual volume of the lungs. After a quiet exhalation, approximately 1,600 ml remains in the lungs. This volume of air is called the functional residual capacity (FRC) of the lungs.

Due to the functional residual capacity (FRC) of the lungs, a relatively constant ratio of oxygen and carbon dioxide is maintained in the alveolar air, since the FRC is several times larger than the tidal volume (TO). Only 2/3 of the airway reaches the alveoli, which is called the volume of alveolar ventilation.

Without external respiration, the human body can usually live up to 5-7 minutes (the so-called clinical death), after which loss of consciousness, irreversible changes in the brain and its death (biological death) occur.

Breathing is one of the few bodily functions that can be controlled consciously and unconsciously.

Functions of the respiratory system

Respiration, gas exchange. The main function of the respiratory organs is to maintain the constancy of the gas composition of the air in the alveoli: remove excess carbon dioxide and replenish the oxygen carried away by the blood. This is achieved through breathing movements. When inhaling, the skeletal muscles expand the chest cavity, followed by the expansion of the lungs, the pressure in the alveoli decreases and the outside air enters the lungs. When you exhale, the chest cavity decreases, its walls squeeze the lungs and the air comes out of them.
Thermoregulation. In addition to ensuring gas exchange, the respiratory organs perform another important function: they participate in heat regulation. When breathing, water evaporates from the surface of the lungs, which leads to cooling of the blood and the whole body.
Voice formation. The lungs create air currents that vibrate the vocal cords of the larynx. Speech is carried out thanks to articulation, which involves the tongue, teeth, lips and other organs that direct sound streams.
Air purification. The inner surface of the nasal cavity is lined with ciliated epithelium. It secretes mucus that moistens the incoming air. Thus, the upper respiratory tract performs important functions: warming, moisturizing and purifying the air, as well as protecting the body from harmful effects through the air.

Lung tissue also plays an important role in processes such as hormone synthesis, water-salt and lipid metabolism. In the abundantly developed vascular system of the lungs, blood is deposited. The respiratory system also provides mechanical and immune protection against environmental factors.

Breathing regulation

Nervous regulation of breathing. Respiration is regulated automatically by the respiratory center, which is represented by a collection of nerve cells located in different parts of the central nervous system. The main part of the respiratory center is located in the medulla oblongata. The respiratory center consists of the centers of inhalation and exhalation, which regulate the work of the respiratory muscles.

Nervous regulation has a reflex effect on breathing. The collapse of the pulmonary alveoli, which occurs during exhalation, reflexively causes inspiration, and the expansion of the alveoli reflexively causes exhalation. Its activity depends on the concentration of carbon dioxide (CO2) in the blood and on nerve impulses coming from the receptors of various internal organs and skin.A hot or cold stimulus (of the sensory system) of the skin, pain, fear, anger, joy (and other emotions and stressors), physical activity quickly change the nature of the respiratory movements.

It should be noted that there are no pain receptors in the lungs, therefore, in order to prevent diseases, periodic fluorographic examinations are carried out.

Humoral regulation of respiration. During muscular work, oxidation processes are enhanced. Consequently, more carbon dioxide is released into the blood. When blood with an excess of carbon dioxide reaches the respiratory center and begins to irritate it, the activity of the center increases. The person begins to breathe deeply. As a result, excess carbon dioxide is removed, and the lack of oxygen is replenished.

If the concentration of carbon dioxide in the blood decreases, the work of the respiratory center is inhibited and involuntary breath holding occurs.

Thanks to nervous and humoral regulation, the concentration of carbon dioxide and oxygen in the blood is maintained at a certain level under any conditions.

With problems with external respiration, certain

Vital capacity of the lungs

The vital capacity of the lungs is an important indicator of respiration. If a person takes the deepest breath, and then exhales as much as possible, then the exchange of exhaled air will be the vital capacity of the lungs. The vital capacity of the lungs depends on age, gender, height, and also on the degree of fitness of a person.

To measure the vital capacity of the lungs, use such a device as - SPIROMETER. For a person, not only the vital capacity of the lungs is important, but also the endurance of the respiratory muscles. A person whose lung capacity is small, and even the respiratory muscles are weak, has to breathe often and superficially. This leads to the fact that fresh air remains mainly in the airways and only a small part of it reaches the alveoli.

Breathing and exercise

During physical exertion, breathing, as a rule, increases. The metabolism is accelerated, the muscles require more oxygen.

Devices for the study of respiratory parameters

capnograph- a device for measuring and graphically displaying the content of carbon dioxide in the air exhaled by a patient over a certain period of time.
pneumograph- a device for measuring and graphically displaying the frequency, amplitude and form of respiratory movements over a certain period of time.
Spirograph- a device for measuring and graphically displaying the dynamic characteristics of respiration.
Spirometer- a device for measuring VC (vital capacity of the lungs).

OUR LUNGS LOVE:

1. Fresh air(with insufficient oxygen supply to the tissues: tissue function is impaired, because the decay and oxidation of organic substances stops, energy ceases to be released, and cells deprived of energy supply die. Therefore, staying in a stuffy room leads to headaches, lethargy, decreased performance ).

2. Exercise(with muscular work, oxidation processes are intensified).

OUR LUNGS DON'T LIKE:

1. Infectious and chronic diseases of the respiratory tract(sinusitis, frontal sinusitis, tonsillitis, diphtheria, influenza, tonsillitis, acute respiratory infections, tuberculosis, lung cancer).

2. Polluted air(automotive exhaust, dust, polluted air, smoke, vodka fumes, carbon monoxide - all these components have an adverse effect on the body. Hemoglobin molecules that have captured carbon monoxide are deprived of the ability to carry oxygen from the lungs to tissues for a long time. There is a lack of oxygen in the blood and tissues, which affects the functioning of the brain and other organs).

3. Smoking(narcogenic substances contained in nicotine are involved in metabolism and interfere with nervous and humoral regulation, disrupting both. In addition, tobacco smoke substances irritate the mucous membrane of the respiratory tract, which leads to an increase in the mucus secreted by it).

And now let's look at and analyze the respiratory process as a whole, and also trace the anatomy of the respiratory tract and a number of other features associated with this process.

Total information

The respiratory system performs the function of gas exchange between the external environment and the body and includes the following organs: the nasal cavity, larynx, trachea, or windpipe, main bronchi and lungs. The conduction of air from the nasal cavity to the larynx and vice versa occurs through the upper parts of the pharynx (nasopharynx and oropharynx), which is studied together with the digestive organs. The nasal cavity, larynx, trachea, main bronchi and their branches inside the lungs serve to conduct inhaled and exhaled air and are air-carrying, or respiratory, ways. External respiration is carried out through them - air is exchanged between the external environment and the lungs. In the clinic, it is customary to call the nasal cavity together with the nasopharynx and larynx the upper respiratory tract, and the trachea and other organs involved in air conduction - the lower respiratory tract. All organs related to the respiratory tract have a solid skeleton, represented in the walls of the nasal cavity by bones of cartilage, and in the walls of the larynx, trachea and bronchi - by cartilage. Thanks to this skeleton, the airways do not collapse and air circulates freely through them during breathing. From the inside, the respiratory tract is lined with a mucous membrane, supplied almost throughout its entire length with ciliated epithelium. The mucous membrane is involved in the purification of the inhaled air from dust particles, as well as in its humidification and combustion (if it is dry and cold). External respiration occurs due to the rhythmic movements of the chest. During inhalation, air enters the alveoli through the airways, and during exhalation, out of the alveoli. Pulmonary alveoli have a structure that differs from the airways (see below), and serve for the diffusion of gases: from the air in the alveoli (alveolar air), oxygen enters the blood, and carbon dioxide is reversed. Arterial blood flowing from the lungs transports oxygen to all organs of the body, and venous blood flowing to the lungs delivers carbon dioxide back.

The respiratory system also performs other functions. So, in the nasal cavity there is an organ of smell, the larynx is an organ of sound production, water vapor is released through the lungs.

nasal cavity

The nasal cavity is the initial section of the respiratory system. Two inlets, the nostrils, lead into the nasal cavity, and through two posterior holes, the choan, it communicates with the nasopharynx. To the top of the nasal cavity is the anterior cranial fossa. To the bottom is the oral cavity, and on the sides are the eye sockets and maxillary sinuses. The cartilaginous skeleton of the nose consists of the following cartilages: lateral cartilage (paired), large alar cartilage (paired), small alar cartilages, cartilage of the nasal septum. In each half of the nasal cavity on the side wall there are three turbinates: top, middle and bottom. The shells share three slit-like spaces: the superior, middle, and inferior nasal passages. There is a common nasal passage between the septum and the turbinates. The anterior smaller part of the nasal cavity is called the nasal vestibule, and the posterior large part is called the nasal cavity proper. The mucous membrane of the nasal cavity covers all its walls of the nasal concha. It is lined with cylindrical ciliated epithelium, contains a large number of mucous glands and blood vessels. The cilia of the ciliated epithelium fluctuate towards the choanoma and contribute to the retention of dust particles. The secret of the mucous glands wets the mucous membrane, while enveloping dust particles and moistening the dry air. Blood vessels form plexuses. Particularly dense plexuses of venous vessels are located in the region of the inferior turbinate and along the edge of the middle turbinate. They are called cavernous and, if damaged, can produce profuse bleeding. The presence of a large number of vessels in the mucosa of the vessels contributes to the warming of the inhaled air. With adverse effects (temperature, chemical, etc.), the nasal mucosa is able to swell, which causes difficulty in nasal breathing. The mucous membrane of the superior nasal concha and the upper part of the nasal septum contains special olfactory and supporting cells that make up the organ of smell, and is called the olfactory region. The mucous membrane of the remaining parts of the nasal cavity makes up the respiratory region (during calm breathing, air passes mainly through the lower and middle nasal passages). Inflammation of the nasal mucosa is called rhinitis (from the Greek Rhinos - nose). External nose (nasus externus). Together with the nasal cavity, the external nose is considered. The nasal bones, frontal processes of the maxillary bones, nasal cartilage and soft tissues (skin, muscles) are involved in the formation of the external nose. In the external nose, the root of the nose, the back and the apex are distinguished. The inferior lateral sections of the external nose, delimited by grooves, are called wings. The size and shape of the external nose varies individually. Paranasal sinuses. In the nasal cavity with the help of holes open maxillary (steam), frontal, wedge-shaped and ethmoid sinuses. They are called paranasal sinuses, or paranasal sinuses. The walls of the sinuses are lined with mucous membrane, which is a continuation of the mucous membrane of the nasal cavity. The paranasal sinuses are involved in warming the inhaled air and are sound resonators. The maxillary sinus (maxillary sinus) is located in the body of the same name bone. The frontal and sphenoid sinuses are located in the corresponding bones and each is divided into two halves by a septum. The ethmoid sinuses are made up of many small cavities - cells; they are divided into anterior, middle and posterior. The maxillary, frontal sinuses and the anterior and middle cells of the ethmoid sinuses open into the middle nasal passage, and the sphenoid sinus and posterior cells of the ethmoid sinuses open into the upper nasal passage. The lacrimal canal opens into the lower nasal passage. It should be borne in mind that the paranasal sinuses in a newborn are absent or very small; their development occurs after birth. In medical practice, inflammatory diseases of the paranasal sinuses are not uncommon, for example, sinusitis - inflammation of the maxillary sinus, frontal sinusitis - inflammation of the frontal sinus, etc.