The respiratory system consists of the following organs. What is the respiratory system?

We inhale air from the atmosphere; The body exchanges oxygen and carbon dioxide, after which the air is exhaled. This process is repeated many thousands of times per day; it is vital to 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 respiratory tract:

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 at the front

Structure of the upper respiratory tract

Nose

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

The nose consists of:

The nasal bone that forms the bridge 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 ciliated mucous membrane, consisting of cells that have cilia that work like a filter. The cuboid cells produce mucus, which traps all 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 mucous membrane, just like the nasal cavity. Mucus retention in the sinuses can cause headaches.

Pharynx

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

The nasopharynx, or nasal section of the pharynx, provides air flow when we breathe through our nose. It is connected to both ears by channels - the Eustachian (auditory) tubes - containing mucus. Through the eustachian tubes, throat infections can easily spread to the ears. The adenoids are located in this section 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 passageway for air inhaled by the mouth and food. It contains tonsils, which, like adenoids, have a protective function.
The laryngopharynx 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 flows further. Here he continues to cleanse himself. The larynx contains cartilage that forms the vocal folds. The cartilage also forms the lid-like epiglottis, which hangs over the entrance to the larynx. The epiglottis prevents food from entering the airways when swallowing.

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 is formed in front by C-shaped hyaline cartilages, connected behind in circles by visceral muscles and connective tissue. These semi-solid structures prevent the trachea from constricting and blocking the air flow. The trachea descends into the chest approximately 12 cm and there diverges into two sections - the right and left bronchi.

Bronchi

The bronchi are pathways 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 and divides 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, the vital process of exchange of oxygen and carbon dioxide occurs.

On the outside, the lungs are covered with a protective membrane, the pleura, which has two layers:

Smooth inner layer attached to the lungs.
Wall outer layer connected to fins and diaphragm.

The smooth and parietal layers of the pleura are separated by the pleural cavity, which contains a liquid lubricant that allows 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 cells in the body 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 breathing process involves five actions: inhalation and exhalation, external respiration, transport, internal respiration and cellular respiration.

Breath

Air enters the body through the nose or mouth.

Breathing through the nose is more effective because:

The air is filtered by cilia, clearing foreign particles. They are thrown back when we sneeze or blow our nose, or enter the hypopharynx and are swallowed.
As the air passes through the nose, it is heated.
The air is humidified 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 downward.
The intercostal muscles contract.
The ribs rise and expand.
The chest cavity increases.
The pressure in the lungs decreases.
Air pressure increases.
Air fills the lungs.
The lungs expand as they fill with air.

Exhalation:

The diaphragm relaxes and returns to its dome shape.
The intercostal muscles relax.
The ribs return to their original position.
The chest cavity returns to its normal shape.
The pressure in the lungs increases.
Air pressure decreases.
Air may escape from the lungs.
The elastic traction of the lung helps displace air.
Contraction of the abdominal muscles increases exhalation, lifting the abdominal organs.

After exhalation, there is a short pause before a new inhalation, 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 breathing rate changes depending on the state of the body. For example, if we need to run to catch the bus, it increases, providing the muscles with enough oxygen to complete this task. After we board the bus, our breathing rate decreases because our muscles' need for oxygen decreases.

External breathing

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 greater pressure than the blood in the surrounding capillaries. Because of this, oxygen can easily pass into the blood, increasing blood pressure. When the pressure equalizes, this process, called diffusion, stops.
Carbon dioxide in the blood, brought from the cells, has a higher 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 release carbon dioxide.
After this, 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 the cells in which gas exchange occurs by diffusion:

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

Oxygen is replaced by carbon dioxide, and the whole cycle begins again.

Cellular respiration

Cellular respiration is the absorption 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 breathing process is decisive for each individual cell, and the frequency and depth of breathing must correspond to the needs of the body. Although breathing is controlled by the autonomic nervous system, certain factors such as stress and poor posture can affect the respiratory system, reducing breathing efficiency. This, in turn, affects the functioning 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 quickens with increasing physical activity, and the client's breathing calms down as they relax.

Possible violations

Possible respiratory system disorders 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 passageways for air. It can be caused by external factors - acquired bronchial asthma, or internal ones - 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 is most susceptible to the age group from 15 to 22 years. Symptoms include persistent sore throat and/or tonsillitis.
croup is a childhood viral infection. Symptoms are fever and severe dry cough.
LARINGITIS - inflammation of the larynx, causing hoarseness and/or loss of voice. There are two types: acute, which develops quickly and passes quickly, and chronic, which recurs periodically.
NASAL POLYP is a harmless growth of mucous membrane in the nasal cavity that contains fluid and obstructs the passage of air.
ARI is a contagious viral infection, the symptoms of which are a sore throat and runny nose. Usually lasts 2-7 days, full recovery may take up to 3 weeks.
PLEURITIS - 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 treat.
PNEUMOTHORAX - collapsed lung (possibly as a result of a ruptured lung).
HAYLINOSIS is a disease caused by an allergic reaction to pollen. Affects the nose, eyes, sinuses: pollen irritates these areas, causing a runny nose, eye inflammation and excess mucus production. The respiratory tract may also be affected, then breathing becomes difficult, with whistling.
LUNG CANCER is a life-threatening malignant tumor of the lungs.
Cleft Palate - deformation 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 stuffy.
SINUSITIS - inflammation of the mucous membrane of the sinuses, causing blockage. Can be very painful and cause inflammation.
STRESS is a condition that causes the autonomous system to increase the release of adrenaline. This causes rapid breathing.
TONSILLITIS - inflammation of the tonsils, causing a sore throat. Occurs more often in children.
TUBERCULOSIS is an infectious disease that causes the formation of nodular thickenings 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 and goes away in about a week. Chronic pharyngitis lasts longer and is typical for smokers. EMPHYSEMA - inflammation of the alveoli of the lungs, causing a slowdown in the flow of blood through the lungs. Usually accompanies bronchitis and/or occurs in old age. The respiratory system plays a vital role in the body.

Knowledge

You should make sure you are breathing correctly, 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.

The following types of breathing exist:

Lateral costal breathing is normal breathing, in which the lungs receive enough oxygen for daily needs. This type of breathing is associated with the aerobic energy system and fills 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 breathing is associated with the anaerobic energy system and leads to oxygen debt and muscle fatigue if energy demands exceed oxygen consumption. Air enters only the upper lobes of the lungs.
Diaphragmatic - deep breathing associated with relaxation, which replenishes any oxygen debt resulting from apical breathing. With it, the lungs can be completely filled with air.

Correct breathing can be learned. Practices such as yoga and tai chi place a lot of emphasis on breathing techniques.

Whenever possible, breathing techniques should accompany procedures and therapy, as they are beneficial for both therapist and patient, clearing the mind and energizing the body.

Begin the procedure with a deep breathing exercise to relieve the patient's stress and tension and prepare him for therapy.
Finishing the procedure with a breathing exercise will allow the patient to see the connection between breathing and stress levels.

Breathing is underestimated and taken for granted. However, special care must be taken to ensure that the respiratory system can perform its functions freely and effectively and does not experience stress and discomfort, which cannot be avoided.

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. participates in the production of hormones;

5. participates in metabolism;

6. participates in immunological protection.

In the airways, the air is warmed or cooled, purified, moistened, and olfactory, temperature and mechanical stimuli are also perceived. The respiratory system begins with the nasal cavity.

The entrance openings to the nasal cavity are the nostrils. The anterior lower wall separates the nasal cavity from the oral cavity, and consists of the soft and hard palate. The posterior wall of the nose is the nasopharyngeal opening (choanae) which passes into the nasopharynx. The nasal plate consists of the anterior ethmoid bone and vomer. From the nasal septum, on different sides there are curved bone plates - the nasal turbinates. The nasolacrimal duct opens into the lower nasal passage.

The mucous membrane is lined with ciliated epithelium and contains a significant number of glands that secrete mucus. There are also many vessels that warm cold air and nerves that perform the olfactory function, which is why it is considered the 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 the IV-VII cervical vertebrae; on the surface of the neck it forms a small (in women) and strongly protruding (in men) elevation - the protrusion of the larynx (Adam's apple, prominent lyngeria). In front, the larynx is suspended at the hyoid bone, below it connects to the trachea. The muscles of the neck lie in front of the larynx, and the neurovascular bundles lie on the side. Consists of cartilage. They are divided into:

1. unpaired (cricoid, thyroid, epiglottis);

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

Laryngeal cartilages.

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 tracheal cartilage using a ligament. It has an arc and a quadrangular plate; the arch of cartilage is directed forward, the plate is directed backward. On the arch of the cricoid cartilage there is hyaline unpaired, the largest cartilage of the larynx - thyroid. Arytenoid cartilage paired, hyaline, similar to a quadrangular pyramid. Horn-shaped And sphenoid cartilage are located in the thickness of the arytenoid ligament.

The cartilages of the larynx are connected to each other by joints and ligaments. Muscles of the larynx. All muscles of the larynx are divided into three groups: dilators, which narrow the glottis and change the tension of the vocal cords. 1. Muscle that expands the glottis - posterior cricoarytenoid(paired muscle);

The larynx has membranes:

1.mucous membrane – 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; vocal cords are shorter, voice timbre is higher. The size of the larynx may change during puberty, leading to changes in voice.

Trachea– this is a tube 10-15 cm long, has 2 parts: cervical and thoracic. The esophagus passes behind, the thyroid gland, thymus, 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 extend into the right and left lungs. This place is called a bifurcation.

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

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

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

Lungs- these are the main organs of the respiratory apparatus, occupying almost the entire chest cavity. They change shape and size depending on the breathing phase. It has the shape of a truncated cone. The apex of the lung faces above the clavicular fossa. At the bottom, the lungs have a concave base. They are adjacent to the diaphragm.

There are three surfaces in the lung: convex, costal 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 grooves: the right one 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 pulmonary vesicle system. A bronchus with a diameter of 1 mm is called lobular. Each alveolar duct ends in two alveolar sacs. The walls of the alveolar sacs consist of the pulmonary alveoli. The diameter of the alveolar duct and alveolar sac is 0.2 - 0.6 mm, the alveoli - 0.25-0.30 mm.

The respiratory bronchioles, as well as the alveolar ducts, 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 m2.

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

Distinguish visceral pleura, which tightly fuses with the lung tissue and extends into the cracks between the lobes of the lung, and parietal, which lines the inside of the chest cavity wall.

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

A slit-like closed space is formed between the parietal and visceral pleura - 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 limited in front by the sternum, in the back by the thoracic spine, and on the sides by the right and left mediastinal pleura. At the top, the mediastinum continues to the superior thoracic aperture, and at the bottom to the diaphragm. There are two sections of the mediastinum: superior and inferior.

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

The importance of this system for humans can hardly be overestimated. You need to think about how the human respiratory system works, what its structure and functions are, before health problems may arise.

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The structure of the human respiratory system

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

The anatomy of the respiratory organs stipulates 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. It moves further through the pharynx, entering the trachea.

The upper respiratory tract includes the paranasal sinuses and 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 the incoming air and cleans it. There is a special mucus here that has protective properties that help fight infection.

The larynx is a cartilaginous formation that is located in the space from the pharynx to 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 classifies them as 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.

The lungs are divided into sections: apex and base. This organ has three surfaces:

diaphragmatic;
mediastinal;
costal

The lung cavity is protected, in short, by the rib cage on the sides and the diaphragm 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 organs is as follows: supply the body with oxygen in order to sufficiently ensure its vital functions, as well as remove carbon dioxide and other breakdown products from the human body by performing gas exchange.

The respiratory system also performs a number of other functions:

Creating air flow to ensure voice formation.
Obtaining air for odor recognition.
The role of breathing is also that it provides ventilation to maintain optimal body temperature;
These organs are also involved in the blood circulation process.
A protective function is carried out against the threat of pathogenic microorganisms entering along with the inhaled air, including when a deep breath occurs.
To a small extent, external respiration helps remove 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 blood deposition.

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 overall plan requires it.

Human breathing mechanism

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

The flow of oxygen into the body can occur through the nose or mouth. It then passes through the pharynx, larynx and into the lungs.

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

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

Air enters the lungs because their volume periodically increases and decreases. The pleura is attached to the diaphragm. Therefore, when the latter expands, the volume of the lungs increases. By taking in air, internal respiration occurs. If the diaphragm contracts, the pleura pushes waste carbon dioxide out.

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

Different types of breathing may occur:

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 contracts while simultaneously lowering slightly.
Abdominal breathing looks different. The inhalation process is carried out due to the expansion of the abdominal muscles with a slight rise of the diaphragm. When 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 may be used during breathing.

Diseases of the human respiratory system

Such diseases usually fall into one of the following categories:

In some cases, the cause may be an infectious infection. The cause may be microbes, viruses, bacteria, which, once in the body, have a pathogenic effect.
Some people experience allergic reactions that result in various breathing problems. There can be many reasons for such disorders, depending on the type of allergy 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 may 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 genetic 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 monitor the presence of a 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 can be dry, with pneumonia it can be wet. If we are talking about ARVI diseases, the cough 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 experiences stress. Objective is expressed in a change in the rhythm and force of breathing.

Importance of the respiratory system

The ability of people to speak is largely based on proper breathing.

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

In addition to carbon dioxide, breathing also removes some other waste products from the human body.

In this way, a person is given the opportunity to distinguish different odors by inhaling air through the nose.

Thanks to this system of the body, gas exchange between a person and the environment takes place, supplies organs and tissues with oxygen and removes waste carbon dioxide from the human body.

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 human external respiration (gas exchange between inhaled atmospheric air and blood circulating in the pulmonary circulation).

Gas exchange takes place 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 baby 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 inhalation is associated with the activity of the muscles of the diaphragm and external intercostal muscles. When you inhale, the diaphragm lowers, the ribs rise, and the distance between them increases. Normal calm exhalation occurs largely passively, with the internal intercostal muscles and some abdominal muscles actively working. When you exhale, the diaphragm rises, the ribs move down, and the distance between them decreases.

Types of breathing

The respiratory system performs only the first part of gas exchange. The rest is done 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 provides gas exchange between blood and tissue cells. It is carried out by the circulatory system, since the blood delivers oxygen to the organs and removes decay products and carbon dioxide from them.

Pulmonary breathing. The exchange of gases in the lungs occurs due to diffusion. The blood entering from the heart into the capillaries that encircle 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 also enters the blood due to diffusion. But in order for this gas exchange to occur 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 with 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, oxyhemoglobin breaks down into hemoglobin and oxygen. Oxygen passes into tissue fluid and is used there by cells for the biological oxidation of organic substances. The energy released in this case is used for the vital processes of cells and tissues.

If there is insufficient oxygen supply to the tissues: the function of the tissue is disrupted because the breakdown 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 simultaneously increase.

Types of breathing

Based on the method of chest expansion, two types of breathing are distinguished:

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

Breathing happens:

deep and superficial;
frequent and rare.

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

System and structure of the respiratory organs

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 one occurs 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 located in hermetically sealed cavities, the walls of which are lined with parietal pleura. Between the parietal and pulmonary pleura there 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.

Having entered the lungs, the main bronchi branch, forming a bronchial tree, at the ends of which there are pulmonary vesicles, alveoli. Along the bronchial tree, air reaches the alveoli, where gas exchange occurs between atmospheric air that has reached the pulmonary alveoli (lung parenchyma) and 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 are carried out by changing the size of the chest using the respiratory muscles. During one breath (at rest), 400-500 ml of air enters the lungs. This volume of air is called tidal volume (TIV). 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 1,200 ml of air remains in the lungs, called residual lung volume. 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.

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

Without external respiration, the human body can usually survive 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 functions of the body that can be controlled consciously and unconsciously.

Functions of the respiratory system

Breathing, gas exchange. The main function of the respiratory organs is to maintain a constant gas composition of the air in the alveoli: remove excess carbon dioxide and replenish oxygen carried away by the blood. This is achieved through breathing movements. When you inhale, the skeletal muscles expand the chest cavity, followed by the lungs, the pressure in the alveoli drops and outside air enters the lungs. When you exhale, the chest cavity decreases, its walls compress the lungs and air leaves 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 entire body.
Voice formation. The lungs create air currents that vibrate the vocal cords of the larynx. Speech is achieved through articulation, which involves the tongue, teeth, lips and other organs that direct sound flows.
Air purification. The inner surface of the nasal cavity is lined with ciliated epithelium. It secretes mucus that moisturizes the incoming air. Thus, the upper respiratory tract performs important functions: warming, humidifying and purifying the air, as well as protecting the body from harmful influences 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. Breathing 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 inhalation and exhalation centers, which regulate the functioning of the respiratory muscles.

Nervous regulation has a reflex effect on breathing. The collapse of the pulmonary alveoli, which occurs during exhalation, reflexively causes inhalation, 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 receptors in various internal organs and skin.A hot or cold irritant (sensory system) of the skin, pain, fear, anger, joy (and other emotions and stressors), physical activity quickly change the nature of 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 muscle work, oxidation processes intensify. Consequently, more carbon dioxide is released into the blood. When blood with excess 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 holding of breath occurs.

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

When problems with external respiration arise, certain

Vital capacity of the lungs

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

To measure the vital capacity of the lungs, a device such as a Spirometer is used. For humans, not only the vital capacity of the lungs is important, but also the endurance of the respiratory muscles. A person whose lung vital capacity is small and whose respiratory muscles are also weak has to breathe frequently and shallowly. 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 activity, breathing usually increases. Metabolism accelerates, muscles require more oxygen.

Instruments for studying breathing parameters

Capnograph- a device for measuring and graphically displaying the carbon dioxide content 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 shape of respiratory movements over a certain period of time.
Spirograph- a device for measuring and graphically displaying the dynamic characteristics of breathing.
Spirometer- a device for measuring vital capacity (vital capacity of the lungs).

OUR LUNGS LOVE:

1. Fresh air(with insufficient oxygen supply to tissues: tissue function is impaired because the breakdown 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, and decreased performance ).

2. Exercises(during muscular work, oxidation processes intensify).

OUR LUNGS DO NOT LIKE:

1. Infectious and chronic respiratory diseases(sinusitis, sinusitis, tonsillitis, diphtheria, influenza, sore throat, acute respiratory infections, tuberculosis, lung cancer).

2. Polluted air(car exhausts, 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 permanently deprived of the ability to transfer oxygen from the lungs to the tissues. 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 included in the metabolism and interfere with nervous and humoral regulation, disrupting both. In addition, substances in tobacco smoke irritate the mucous membrane of the respiratory tract, which leads to an increase in mucus secreted by it).

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 passage of air from the nasal cavity to the larynx and back 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 airways, or respiratory tracts. Through them, external respiration is carried out - the exchange of air 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 conducting air - the lower respiratory tract. All organs related to the respiratory tract have a hard skeleton, represented by cartilage bones in the walls of the nasal cavity, and cartilage in the walls of the larynx, trachea and bronchi. Thanks to this skeleton, the airways do not collapse and air circulates freely during breathing. The inside of the respiratory tract is lined with a mucous membrane, supplied almost throughout its entire length with ciliated epithelium. The mucous membrane is involved in purifying 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 flows through the airways into the alveoli, and during exhalation, it flows out from the alveoli. Pulmonary alveoli have a structure that differs from the airways (see below) and serve for the diffusion of gases: oxygen enters the blood from the air in the alveoli (alveolar air), and carbon dioxide flows back. 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. Thus, in the nasal cavity there is an organ of smell, the larynx is an organ of sound production, and water vapor is released through the lungs.

Nasal cavity

The nasal cavity is the initial section of the respiratory system. Two entrance openings lead into the nasal cavity - the nostrils, and through two posterior openings - the choana, it communicates with the nasopharynx. Towards the top of the nasal cavity is the anterior cranial fossa. To the bottom is the oral cavity, and on the sides are the orbits and maxillary sinuses. The cartilaginous skeleton of the nose consists of the following cartilages: lateral cartilage (paired), large cartilage of the nasal wing (paired), small wing cartilages, cartilage of the nasal septum. In each half of the nasal cavity on the lateral wall there are three nasal conchae: top, middle and bottom. The shells are separated by three slit-like spaces: the upper, middle and lower nasal passages. Between the septum and the nasal turbinates there is a common nasal passage. The anterior smaller part of the nasal cavity is called the vestibule of the nose, and the posterior larger part is called the nasal cavity itself. The mucous membrane of the nasal cavity covers all its walls - the turbinates. It is lined with columnar ciliated epithelium and contains a large number of mucous glands and blood vessels. The cilia of the ciliated epithelium oscillate towards the choanae and help retain dust particles. The secretion of the mucous glands moistens the mucous membrane, while enveloping dust particles and moisturizing dry air. Blood vessels form plexuses. Particularly dense plexuses of venous vessels are located in the area of the inferior nasal concha and along the edge of the middle nasal concha. They are called cavernous and, if damaged, can cause heavy bleeding. The presence of a large number of vessels in the mucous membrane of the blood vessels helps to warm the inhaled air. Under adverse influences (temperature, chemical, etc.), the nasal mucosa can swell, which causes difficulty in nasal breathing. The mucous membrane of the superior turbinate and the upper part of the nasal septum contains special olfactory and supporting cells that make up the olfactory organ, and is called the olfactory region. The mucous membrane of the remaining parts of the nasal cavity makes up the respiratory region (during quiet 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). The external nose is examined together with the nasal cavity. The formation of the external nose involves the nasal bones, frontal processes of the maxillary bones, nasal cartilage and soft tissues (skin, muscles). The external nose is divided into the root of the nose, the back and the apex. The inferolateral sections of the external nose, delimited by grooves, are called wings. The size and shape of the external nose varies individually. Paranasal sinuses. Open into the nasal cavity using holes maxillary (paired), frontal, sphenoid and ethmoid sinuses. They are called the 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 bone of the same name. The frontal and sphenoid sinuses are located in the corresponding bones and each is divided into two halves by a septum. The ethmoid sinuses consist of many small cavities - cells; they are divided into front, middle and rear. The maxillary, frontal sinuses and the anterior and middle cells of the ethmoid sinuses open into the middle meatus, and the sphenoid sinus and the posterior cells of the ethmoid sinuses open into the superior meatus. The nasolacrimal duct opens into the lower nasal passage. It should be borne in mind that the paranasal sinuses in a newborn are absent or very small in size; 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.