The respiratory organs are several organs united into a single bronchial-pulmonary system. It consists of two departments:

The respiratory tract through which air passes;
the lungs themselves. The respiratory tract is usually divided into:
upper respiratory tract - nose, paranasal sinuses nose, throat, eustachian tubes and some other entities;
the lower respiratory tract - the larynx, the bronchial system from the largest bronchus in the body - the trachea to its smallest branches, which are usually called bronchioles.

Functions of the respiratory tract in the body

Respiratory tract:

They carry air from the atmosphere to the lungs;
clean air masses from dust pollution;
protect the lungs from harmful effects(some bacteria, viruses, foreign particles, etc. settle on the mucous membrane of the bronchi and are then removed from the body);
warm and humidify the inhaled air.

The lungs themselves look like many small air-inflated sacs (alveoli), interconnected and similar to bunches of grapes. The main function of the lungs is the process of gas exchange, that is, the absorption of oxygen from the atmospheric air - a gas vital for the normal, harmonious operation of all body systems, as well as the release of waste gases and, above all, carbon dioxide into the atmosphere.

All these essential functions respiratory organs can be seriously impaired by diseases bronchopulmonary system.

The respiratory organs of children are different from the respiratory organs of adults. These structural features and functions of the bronchopulmonary system must be taken into account when carrying out hygienic, preventive and therapeutic measures in a child.

Let us dwell on some age-related features of the structure and function of the respiratory organs.

Human respiratory organs

Hoc is the "watchdog" of the respiratory tract. The nose is the first to take on the attack of all harmful external influences.

The nose is the center of information about the state of the surrounding atmosphere. It has a complex internal configuration and performs a variety of functions:

Air passes through it;
It is in the nose that the inhaled air is heated and humidified to the parameters necessary for the internal environment of the body;
the bulk of atmospheric pollution, microbes and viruses is primarily deposited on the nasal mucosa;
In addition, the nose is an organ that provides the sense of smell, that is, it has the ability to sense odors.

What provides the child normal breathing through the nose

Normal nasal breathing extremely important for children of any age. It is a barrier to infection entering the respiratory tract, and therefore to the occurrence of bronchopulmonary diseases. Well heated clean air- guarantee of protection against colds. In addition, the sense of smell develops a child’s understanding of the external environment, is protective in nature, and forms an attitude towards food and appetite.

Nasal breathing is physiologically correct breathing. It is necessary to ensure that the child breathes through his nose. Breathing through the mouth in the absence or severe difficulty of nasal breathing is always a sign of a nasal disease and requires special treatment.

Features of the nose in children

The nose in children has a number of features.

The nasal cavity is relatively small. How smaller child, the smaller the nasal cavity.
The nasal passages are very narrow.
The nasal mucosa is loose and well supplied with blood vessels, so any irritation or inflammation leads to rapid swelling and a sharp decrease in the lumen of the nasal passages, up to their complete obstruction.
Nasal mucus, which is constantly produced by the mucous glands of the child’s nose, is quite thick. Mucus often stagnates in the nasal passages, dries out and leads to the formation of crusts, which, blocking the nasal passages, also contribute to the disruption of nasal breathing. At the same time, the child begins to “sniff” through his nose or breathe through his mouth.

Genius is one percent inspiration and ninety-nine percent perspiration.

Thomas Edison

October 1979. I worked as a senior resident on the thoracic surgery team at Harefield Hospital in London.

The training program for cardiac surgeons included mandatory operations on the lungs and esophagus, which meant having to deal with cancer, which was very depressing for me. Too often it turned out that the disease had spread throughout the body, and for most patients the prognosis was very sad, so they were not very cheerful either. Among other things, the work turned out to be depressingly monotonous. The choice, as a rule, was meager: remove half a lung or an entire lung, cut out the right or left lung, or the lower or top part esophagus. After you perform each of these actions a hundred times, your enthusiasm does not increase.

However, occasionally more complex cases came across. This was the case for Mario, a forty-two-year-old engineer from Italy working in Saudi Arabia. A cheerful family man, Mario traveled to this southern kingdom in the hope of saving enough money to buy a house. For days on end he worked on a giant industrial complex, located on the outskirts of Jeddah, under the scorching rays of the desert sun.

And then the irreparable happened. While he was working in a confined space, a huge steam boiler suddenly exploded, filling the air with superheated water vapor. Ferry under high pressure. Mario's face was scalded and the walls of his trachea and bronchi were burned.

He almost died on the spot from shock. The steam-cooked tissue was dead, and the mucous membrane peeled off in layers from the walls of the bronchi. All these debris had to be removed, which was done using an outdated, rigid bronchoscope - a long brass tube with a light at one end, which was inserted down the throat, along the back of the throat and vocal cords, and then down the airway.

To prevent Mario from suffocating, the procedure was repeated regularly, almost every day, but pushing the bronchoscope back and forth through the larynx became more and more difficult each time. Soon, so much scar tissue formed that the bronchoscope could no longer fit through, and a tracheostomy was required - surgically create a hole in the neck through which Mario could breathe.

The problem was that the dead bronchial mucosa was quickly replaced by inflamed tissue, and cellular accumulations began to fill the airways like calcium deposits that prevent fluid from flowing through the pipes. Mario could no longer breathe and his condition was steadily deteriorating.

I answered a call from Jeddah. The combustiologist (burn specialist) who treated Mario described this terrible situation in detail and asked us for advice. The only thing I could suggest was to fly the patient to Heathrow so we could try to save his life. The very next day construction company organized his transportation, and he ended up in our hospital.

By that time, my boss was nearing the end of his career, and he happily gave me all the cases that I was ready to take on. And I didn’t refuse anything. I didn't know fear. But it was a complete nightmare. And I asked that we examine the trachea together, after which we tried to figure something out.

Mario looked pathetic. He was breathing with difficulty, making terrible gurgling sounds that arose from the infected foam oozing from the tracheostomy tube. His scarlet face was badly burned. It was covered with a crust, dead skin was peeling off in shreds, and serous fluid was oozing in places.

The patient was burned inside and out; due to the tissue growing in the trachea, he was in danger of dying from suffocation. We put Mario under anesthesia, briefly putting him out of his misery.

While he was unconscious, I used suction to clear the sticky, blood-streaked secretion from the hole in his neck, connected a manual ventilator to the tracheostomy tube, and began squeezing the black rubber bulb. The lungs could hardly fill with air. I decided that a non-flexible bronchoscope should be inserted traditional way- directly through the vocal cords and larynx. This is akin to swallowing a sword - with the difference that it passes through the respiratory tract, and not through the esophagus.

We needed to see the entire trachea, as well as both main bronchi - right and left. To do this, the patient's head had to be tilted back at a certain angle to expose the vocal cords located at the back of the throat.

We tried our best not to knock out Mario's teeth. Because there used to be a perpetual shortage of physical therapists, this method was used to remove fluid from the lungs after lung surgery while keeping patients conscious. It's rough, but it's better than letting the patient choke.

I carefully pushed the rigid telescopic tube past the teeth, along the base of the tongue, and then began to look for the small cartilage - the epiglottis - that protects the entrance to the larynx when we swallow. If you lift it by the edge using a bronchoscope, you can find white, shiny vocal cords with a vertical gap between them. This is the path leading to the trachea.

I have done this procedure hundreds of times when performing biopsies to diagnose lung cancer. Or to remove stuck peanuts. In this case, the entire larynx was burned, and the inflamed vocal cords resembled sausages and looked scary - it was impossible to squeeze through them. Mario was completely dependent on the tracheostomy tube.

I stepped aside, holding the bronchoscope in place so my boss could see what was going on there too. He groaned and shook his head:

I took aim again, brought the end of the bronchoscope to where the gap between the ligaments should be, and pushed it in with force. The swollen vocal cords separated and the instrument hit the tracheostomy tube. We connected the ventilator to the side of the bronchoscope and pulled out the tube that was in the way. In theory, we should have seen the trachea in its entire length, right up to the place where it divides into the main bronchi. But not this time.

The airways were almost destroyed by the overgrown cells, so I continued to lower the rigid instrument downwards, using suction to remove the blood and damaged tissue and at the same time pumping oxygen into the lungs through the bronchoscope. I hoped that the burns would end, and finally, having reached the middle of both main bronchi, we saw the intact walls of the respiratory tract. The problem was that now the injured walls of the bronchi were oozing blood.

Mario's bright red face turned purple and continued to rapidly turn blue, so my boss took matters into his own hands. He began to peer into the tube, periodically inserting a long spotting scope to see better. The situation was extremely dangerous and we had absolutely no idea what to do. To live, a person needs to breathe. Fortunately, the bleeding gradually stopped, and after we removed the blood mixed with sputum, the airway began to look much better.

We put the tracheostomy tube back in and put Mario back on the ventilator. The chest on both sides continued to move, and air entered both lungs. This was already an achievement, but it was still unclear what to do next. We agreed that the prognosis was very unfavorable.

Two days later, Mario's left lung deflated and we repeated the same procedure. It didn't get any better. The tissue continued to grow inexorably. Connected to a ventilator, Mario remained conscious, but he had a hard time.

Death by suffocation is the most unpleasant. I remember how my grandmother died, suffocating from a thyroid tumor. She was supposed to have a tracheostomy, but the operation had to be canceled, and the grandmother sat on the bed for days, barely gasping for air. I remember trying to help her. Why couldn't the tube be placed lower - where the airways remained clear? Why can't tracheostomy tubes be made longer? I was told over and over again that this was impossible.

From what I saw through the bronchoscope, Mario's situation was almost identical. It was necessary to somehow bypass the entire trachea and both main bronchi, otherwise a painful death awaited him in a matter of days. We couldn't clear the airway with the bronchoscope over and over again. The old woman with the scythe was victorious - she was already preparing to take her next victim with her.

Even I, a born optimist, doubted that we were able to do anything. Could we make a bifurcated tube to bypass the damaged airway? My boss said that this was impossible because the tube would immediately become clogged with secretions. Otherwise, of course, this method would have long been used in the treatment of cancer patients.

Then something occurred to me: A Boston company, Hood Laboratories, had come out with a silicone rubber tube with a tracheostomy arm, called the Montgomery T-stent, after the otolaryngologist who invented it. Maybe we should talk to the company and describe the problem we are facing.

That day, while giving Mario another bronchoscopy, I measured how long the tube was needed to reach both main bronchi and called Hood Laboratories that evening. It was a small family business, and its head confirmed that no one had tried this approach before, but agreed to make a bifurcated tube of the required dimensions. I said that the tube was urgently needed. Delighted by the opportunity to help with a unique case, the company's employees delivered it in less than a week. Now we had to figure out how to install it.

It was necessary to insert the branched ends of the tube along the guide wires into both main bronchi simultaneously. However, the wire was too sharp and could damage the thin silicone rubber, so it was necessary to replace it with something safer. Using rubber probes, we have repeatedly moved apart the narrowed areas of the esophagus. The narrowest probes we had fit into the bifurcated tube sent to me and even passed through the lower branches.

I could insert the probes one at a time through the damaged trachea into the bronchi, and then, using them as guides, push the tube itself. I sketched step by step description method I invented and showed the drawings to other thoracic surgeons. Everyone agreed that there was nothing to lose. Only a crazy innovative solution could save Mario's life.

The next day he was taken to the operating room. Having removed the tracheostomy tube, we inserted a rigid bronchoscope into the burned larynx. This time I acted especially carefully so that there was as little blood as possible.

We surgically widened the tracheostomy opening through which we planned to insert our fancy tube, then inserted rubber probes into the right and left bronchi, directly monitoring what was happening through the telescope and not forgetting to diligently pump one hundred percent oxygen into the lungs after each action. So far everything was going well.

I coated the silicone rubber with Vaseline and pushed the tube down with force. The bronchial branches of the tube diverged to the sides at the bifurcation of the trachea and went inside all the way. It couldn't be better. We crossed our fingers, and my boss, with a sharp, decisive movement, pushed the bronchoscope into the larynx.

Always famous for his Irish temperament, he exclaimed:

Damn it, just look! You're a fucking genius, Westaby!

The trachea, which was falling apart, was replaced by a clean white silicone tube, the branches of which sat perfectly in the bronchi. The tube was not kinked or compressed anywhere, and a healthy airway began below it.

Meanwhile, Mario managed to turn blue from hypoxia. We were so excited that we completely forgot to pump oxygen into his lungs, so we set to work with double zeal. Fortunately, now this was not particularly difficult: the wide rubber airways made the task much easier. A real sensation!

We didn't know if this solution would be durable - time will tell. Everything depended on whether Mario had the strength to cough up secretions through the tube, and we could only remove them with suction and continue to ventilate the lungs through the side branch of the tube. When the swelling goes down from the larynx and vocal cords, we will close this hole with a rubber stopper. Then Mario will be able to breathe and speak through his own larynx, if, of course, it is restored. The situation was still highly uncertain, but at least Mario was safe now. He could breathe. Fifteen minutes later he came to his senses and felt incredibly better.

I should have been incredibly happy that my plan was brought to life, but there was no trace of joy here. It was painful in my soul. I recently gave birth to a wonderful daughter, Gemma, but I hardly saw her. I lived in a hospital. This slowly gnawed at me from the inside, and to compensate for the painful feeling, I fanatically operated on everything that came to my hand. I was always ready, but at the same time I was as if possessed by a painful restlessness.

Meanwhile, Mario began to recover, although the lack of a voice made his life much more difficult. He successfully coughed up secretions through the tube, preventing it from becoming clogged (and everyone thought this was impossible), and he was sent to Italy - home to his family.

I was pleased to learn that Hood Laboratories began producing the “T-Y stent” I had invented, calling it the Westaby tube. We began to use this tube extensively for lung cancer patients who were at risk of lower airway obstruction, and thus relieved them of the terrible, painful suffocation that my grandmother had to endure. Why couldn't anyone come up with something like that when she needed help so badly and I was in complete despair?

I don't know how many Westaby pipes were produced, but my brainchild was on the list of products offered by Hood Laboratories for many years. The sketches I made were published in a thoracic surgery journal, and they became visual aid for other surgeons.

While practicing thoracic surgery, I continued to use these tubes for serious problems with the airways, often as a temporary solution until the tumor shrinks due to radiation therapy or anti-cancer drugs. This was my grandmother's legacy. And then a unique opportunity presented itself to use artificial airways in cardiac surgery in conjunction with a heart-lung machine.

The respiratory system is a set of organs and anatomical structures that ensure the movement of air from the atmosphere into the lungs and back (breathing cycles inhalation - exhalation), as well as gas exchange between the air entering the lungs and the blood.

Respiratory organs are the upper and lower respiratory tract and lungs, consisting of bronchioles and alveolar sacs, as well as arteries, capillaries and veins of the pulmonary circulation.

The respiratory system also includes the chest and respiratory muscles (the activity of which ensures stretching of the lungs with the formation of inhalation and exhalation phases and changes in pressure in the pleural cavity), and in addition - the respiratory center located in the brain, peripheral nerves and receptors involved in the regulation of respiration.

The main function of the respiratory organs is to ensure gas exchange between air and blood by diffusion of oxygen and carbon dioxide through the walls of the pulmonary alveoli into the blood capillaries.

Diffusion- a process as a result of which gas from an area of ​​more high concentration tends to an area where its concentration is low.

A characteristic feature of the structure of the respiratory tract is the presence of a cartilaginous base in their walls, as a result of which they do not collapse

In addition, the respiratory organs are involved in sound production, smell detection, the production of certain hormone-like substances, lipid and water-salt metabolism, and maintaining the body's immunity. In the airways, the inhaled air is cleansed, moistened, warmed, as well as the perception of temperature and mechanical stimuli.

Airways

Airways respiratory system begin with the external nose and nasal cavity. The nasal cavity is divided by the osteochondral septum into two parts: right and left. The inner surface of the cavity, lined with mucous membrane, equipped with cilia and penetrated by blood vessels, is covered with mucus, which retains (and partially neutralizes) microbes and dust. Thus, the air in the nasal cavity is purified, neutralized, warmed and moistened. This is why you need to breathe through your nose.

During life nasal cavity traps up to 5 kg of dust

Having passed pharyngeal part airways, air enters the next organ larynx, having the shape of a funnel and formed by several cartilages: the thyroid cartilage protects the larynx in front, the cartilaginous epiglottis closes the entrance to the larynx when swallowing food. If you try to speak while swallowing food, it can get into your airways and cause suffocation.

When swallowing, the cartilage moves upward and then returns to its original place. With this movement, the epiglottis closes the entrance to the larynx, saliva or food goes into the esophagus. What else is there in the larynx? Vocal cords. When a person is silent, the vocal cords diverge; when he speaks loudly, the vocal cords are closed; if he is forced to whisper, the vocal cords are slightly open.

1. Trachea;
2. Aorta;
3. Main left bronchus;
4. Right main bronchus;
5. Alveolar ducts.

The length of the human trachea is about 10 cm, the diameter is about 2.5 cm

From the larynx, air enters the lungs through the trachea and bronchi. The trachea is formed by numerous cartilaginous half-rings located one above the other and connected by muscle and connective tissue. Open ends half rings are adjacent to the esophagus. In the chest, the trachea divides into two main bronchi, from which secondary bronchi branch, which continue to branch further to the bronchioles (thin tubes with a diameter of about 1 mm). The branching of the bronchi is a rather complex network called the bronchial tree.

The bronchioles are divided into even thinner tubes - alveolar ducts, which end in small thin-walled (the thickness of the walls is one cell) sacs - alveoli, collected in clusters like grapes.

Mouth breathing causes deformation of the chest, hearing impairment, disruption of the normal position of the nasal septum and the shape of the lower jaw

The lungs are the main organ of the respiratory system

The most important functions of the lungs are gas exchange, supplying oxygen to hemoglobin, and removing carbon dioxide, or carbon dioxide, which is the end product of metabolism. However, the functions of the lungs are not limited to this alone.

The lungs are involved in maintaining a constant concentration of ions in the body; they can remove other substances from it, except toxins ( essential oils, aromatic substances, “alcohol trail”, acetone, etc.). When you breathe, water evaporates from the surface of the lungs, which cools the blood and the entire body. In addition, the lungs create air currents, vibrating the vocal cords of the larynx.

Conventionally, the lung can be divided into 3 sections:

1. pneumatic ( bronchial tree), through which air, as if through a system of channels, reaches the alveoli;
2. the alveolar system in which gas exchange occurs;
3. circulatory system of the lung.

The volume of inhaled air in an adult is about 0 4-0.5 liters, and the vital capacity of the lungs, that is, the maximum volume, is approximately 7-8 times greater - usually 3-4 liters (in women less than in men), although in athletes it can exceed 6 liters

1. Trachea;
2. Bronchi;
3. Apex of the lung;
4. Upper lobe;
5. Horizontal slot;
6. Average share;
7. Oblique slot;
8. Lower lobe;
9. Heart tenderloin.

The lungs (right and left) lie in chest cavity on both sides of the heart. The surface of the lungs is covered with a thin, moist, shiny membrane, the pleura (from the Greek pleura - rib, side), consisting of two layers: the inner (pulmonary) covers the surface of the lung, and the outer (parietal) covers the inner surface of the chest. Between the sheets, which almost touch each other, there is a hermetically closed slit-like space called the pleural cavity.

In some diseases (pneumonia, tuberculosis), the parietal layer of the pleura can grow together with the pulmonary layer, forming so-called adhesions. At inflammatory diseases accompanied by excessive accumulation of fluid or air in the pleural fissure, it expands sharply and turns into a cavity

The spindle of the lung protrudes 2-3 cm above the collarbone, extending into the lower region of the neck. The surface adjacent to the ribs is convex and has the greatest extent. The inner surface is concave, adjacent to the heart and other organs, convex and has the greatest extent. The inner surface is concave, adjacent to the heart and other organs located between the pleural sacs. On it there is the gate of the lung, a place through which the main bronchus and pulmonary artery enter the lung and two pulmonary veins exit.

Each lung pleural grooves are divided into lobes: the left into two (upper and lower), the right into three (upper, middle and lower).

Lung tissue is formed by bronchioles and many tiny pulmonary vesicles of the alveoli, which look like hemispherical protrusions of the bronchioles. The thinnest walls of the alveoli are a biologically permeable membrane (consisting of a single layer of epithelial cells surrounded by a dense network of blood capillaries), through which gas exchange occurs between the blood in the capillaries and the air filling the alveoli. The inside of the alveoli is coated with a liquid surfactant (surfactant), which weakens the forces of surface tension and prevents the complete collapse of the alveoli during exit.

Compared to the lung volume of a newborn, by the age of 12 the lung volume increases 10 times, by the end of puberty - 20 times

The total thickness of the walls of the alveoli and capillary is only a few micrometers. Thanks to this, oxygen easily penetrates from the alveolar air into the blood, and carbon dioxide easily penetrates from the blood into the alveoli.

Respiratory process

Breathing represents complex process gas exchange between the external environment and the body. The inhaled air differs significantly in composition from the exhaled air: from external environment oxygen enters the body necessary element for metabolism, and carbon dioxide is released outside.

Stages of the respiratory process

• filling the lungs with atmospheric air (pulmonary ventilation)
• the transition of oxygen from the pulmonary alveoli into the blood flowing through the capillaries of the lungs, and the release of carbon dioxide from the blood into the alveoli, and then into the atmosphere
• delivery of oxygen from the blood to the tissues and carbon dioxide from the tissues to the lungs
• oxygen consumption by cells

The processes of air entering the lungs and gas exchange in the lungs are called pulmonary (external) respiration. Blood brings oxygen to cells and tissues, and carbon dioxide from tissues to the lungs. Constantly circulating between the lungs and tissues, blood thus ensures a continuous process of supplying cells and tissues with oxygen and removing carbon dioxide. In the tissues, oxygen leaves the blood to the cells, and carbon dioxide is transferred from the tissues to the blood. This process of tissue respiration occurs with the participation of special respiratory enzymes.

Biological meanings of respiration

• providing the body with oxygen
• removal of carbon dioxide
• oxidation of organic compounds with the release of energy, necessary for a person for life
• removal of metabolic end products (water vapor, ammonia, hydrogen sulfide, etc.)

Mechanism of inhalation and exhalation. Inhalation and exhalation occur through movements of the chest (chest breathing) and the diaphragm (abdominal breathing). The ribs of the relaxed chest fall down, thereby reducing its internal volume. Air is forced out of the lungs, similar to air being forced out of an air pillow or mattress under pressure. By contracting, the respiratory intercostal muscles raise the ribs. The chest expands. The diaphragm, located between the chest and abdominal cavity, contracts, its tubercles are smoothed out, and the volume of the chest increases. Both pleural layers(pulmonary and costal pleura), between which there is no air, transmit this movement to the lungs. A vacuum occurs in the lung tissue, similar to that, which appears when the accordion is stretched. Air enters the lungs.

The respiratory rate of an adult is normally 14-20 breaths per 1 min, but with significant physical activity it can reach up to 80 breaths per 1 min.

When the respiratory muscles relax, the ribs return to starting position and the diaphragm loses tension. The lungs compress, releasing exhaled air. In this case, only a partial exchange occurs, because it is impossible to exhale all the air from the lungs.

During quiet breathing, a person inhales and exhales about 500 cm 3 of air. This amount of air constitutes the tidal volume of the lungs. If you take an additional deep breath, about 1500 cm 3 of air will enter the lungs, called the inspiratory reserve volume. After a calm exhalation, a person can exhale about 1500 cm 3 of air - the reserve volume of exhalation. The amount of air (3500 cm 3), which consists of the tidal volume (500 cm 3), the inspiratory reserve volume (1500 cm 3), and the exhalation reserve volume (1500 cm 3), is called the vital capacity of the lungs.

Out of 500 cm 3 of inhaled air, only 360 cm 3 passes into the alveoli and releases oxygen into the blood. The remaining 140 cm 3 remains in the airways and does not participate in gas exchange. Therefore, the airways are called “dead space”.

After a person exhales a tidal volume of 500 cm3) and then exhales deeply (1500 cm3), there is still approximately 1200 cm3 of residual air volume left in his lungs, which is almost impossible to remove. Therefore, lung tissue does not sink in water.

Within 1 minute, a person inhales and exhales 5-8 liters of air. This is the minute volume of breathing, which during intensive physical activity can reach 80-120 liters per minute.

Trained, physically developed people the vital capacity of the lungs can be significantly greater and reach 7000-7500 cm 3 . Women have a smaller lung capacity than men

Gas exchange in the lungs and transport of gases by blood

The blood that flows from the heart into the capillaries that encircle the pulmonary alveoli contains a lot of carbon dioxide. And in the pulmonary alveoli there is little of it, therefore, thanks to diffusion, it leaves the bloodstream and passes into the alveoli. This is also facilitated by the internally moist walls of the alveoli and capillaries, consisting of only one layer of cells.

Oxygen also enters the blood due to diffusion. There is little free oxygen in the blood, because it is continuously bound by hemoglobin found in red blood cells, turning into oxyhemoglobin. The blood that has become arterial leaves the alveoli and travels through the pulmonary vein to the heart.

In order for gas exchange to take place continuously, it is necessary that the composition of gases in the pulmonary alveoli be constant, which is maintained pulmonary breathing: excess carbon dioxide is removed outside, and the oxygen absorbed by the blood is replaced with oxygen from a fresh portion of the outside air

Tissue respiration occurs in capillaries great circle blood circulation, where the blood gives off oxygen and receives carbon dioxide. There is little oxygen in the tissues, and therefore oxyhemoglobin breaks down into hemoglobin and oxygen, which passes into the tissue fluid and is used there by cells for biological oxidation organic matter. The energy released in this case is intended for the vital processes of cells and tissues.

A lot of carbon dioxide accumulates in tissues. It enters the tissue fluid, and from it into the blood. Here, carbon dioxide is partially captured by hemoglobin, and partially dissolved or chemically bound by blood plasma salts. Venous blood carries it into the right atrium, from there it enters the right ventricle, which pulmonary artery pushes out the venous circle and closes. In the lungs, the blood again becomes arterial and, returning to the left atrium, enters the left ventricle, and from it into the systemic circulation.

The more oxygen is consumed in the tissues, the more oxygen is required from the air to compensate for the costs. That's why when physical work At the same time, both cardiac activity and pulmonary respiration increase.

Thanks to amazing property hemoglobin combines with oxygen and carbon dioxide; the blood is able to absorb these gases in significant quantities

In 100 ml arterial blood contains up to 20 ml of oxygen and 52 ml of carbon dioxide

Action carbon monoxide on the body. Hemoglobin in red blood cells can combine with other gases. Thus, with carbon monoxide (CO) - carbon monoxide formed during incomplete combustion of fuel, hemoglobin combines 150 - 300 times faster and more firmly than with oxygen. Therefore, even with a small content of carbon monoxide in the air, hemoglobin combines not with oxygen, but with carbon monoxide. At the same time, the supply of oxygen to the body stops, and the person begins to suffocate.

If there is carbon monoxide in the room, a person suffocates because oxygen does not enter the body tissues

Oxygen starvation - hypoxia- can also occur when the hemoglobin content in the blood decreases (with significant blood loss), or when there is a lack of oxygen in the air (high in the mountains).

When hit foreign body into the respiratory tract, with swelling of the vocal cords due to the disease, respiratory arrest may occur. Choking develops - asphyxia. When breathing stops, artificial respiration is performed using special devices, and in their absence, using the “mouth to mouth”, “mouth to nose” method or special techniques.

Breathing regulation. Rhythmic, automatic alternation of inhalations and exhalations is regulated from respiratory center located in the medulla oblongata. From this center, impulses: travel to the motor neurons of the vagus and intercostal nerves, which innervate the diaphragm and other respiratory muscles. The work of the respiratory center is coordinated by the higher parts of the brain. Therefore, a person can short time hold or intensify your breathing, as happens, for example, when talking.

The depth and frequency of breathing is affected by the content of CO 2 and O 2 in the blood. These substances irritate the chemoreceptors in the walls of large blood vessels, nerve impulses from them enter the respiratory center. With an increase in CO2 content in the blood, breathing deepens; with a decrease in CO2, breathing becomes more frequent.

1 What is the significance of the breakdown and oxidation of organic cell substances (biological oxidation) for the body?

2 Where do the respiratory organs deliver oxygen - to the alveoli of the lungs or to the cells and tissues of the body?
3 Name the respiratory tract through which air passes?
4 What is the function of the larynx?

Help please!!Very urgent!!

Tests on the topic: “Respiratory organs. Gas exchange"
A - midbrain
B - spinal cord
B - lungs
G - medulla oblongata?
By what mechanisms are respiratory movements carried out?
A - consciousness
B - due to changes in O2 concentration in the blood
B - due to changes in the concentration of CO2 in the blood
G - due to vegetative activity nervous system?
What muscles are involved in respiratory movements:
A – dorsal
B – abdominal
B – intercostal
G – diaphragm?
What causes the diffusion of oxygen from the alveoli into the capillaries:
A – pressure difference
B – concentration difference
B – presence of through holes?
What the lungs are covered with on the outside:
A – fascia
B – parietal pleura
IN - muscle tissue
D – pulmonary pleura?
What is the pressure in the pleural cavity:
A – equal to atmospheric
B – below atmospheric
B – above atmospheric?
Where is oxygen absorbed:
A – nasopharynx
B – lungs
B – red blood cells
D – cell mitochondria?
What is the meaning of breathing:
A – cooling the body
B – CO2 removal
B – oxidation nutrients
G – release of energy?
How does oxyhemoglobin move from the lungs to the cells of the body:
A – small circle vessels
B – vessels of the great circle
B – bypassing the heart
G – through the heart?
How many pleural cavities does a person have?
A – one, common to both lungs
B – two, each lung is in its own
Q – no pleural cavities?

Option II:
When the vocal cords diverge most widely:
A - the person is silent
B – speaks in a whisper
B – speaks loudly
G – screaming?
How is the epiglottis positioned during swallowing?
A – lowered, closes the entrance to the larynx
B – raised, does not cover the entrance to the larynx
B – lowered, covering the entrance to the trachea?
From which organ does air enter the larynx during inhalation?
A – from the nasal cavity
B – from the nasopharynx
B – from the oral cavity?
What features of the trachea ensure the free passage of air into the bronchi:
A – cartilaginous semirings
B – cartilaginous rings
B – cartilaginous spiral of the trachea?
What are the names of the final structures of the respiratory tract in which gas exchange occurs:
A – bronchi
B – bronchioles
B – alveoli?
Does not allow food to enter the larynx:
A – mucous membrane
B – epiglottis
B – cartilaginous half rings?
Contains vocal cords inside:
A – larynx
B – bronchi
B – nasal cavity?
Longest part airway:
A – larynx
B – trachea
B – bronchi?
Site of gas exchange between lungs and blood:
A – bronchi
B – lungs
B – pulmonary vesicles?
Lines the outer surface of the lungs:
A – mucous membrane
B – connective tissue
B – pleura?

Option III:
How much oxygen is in the inhaled air:
A – 0.03%
B – 4%
B – 16%
G – 21%
How much oxygen is in exhaled air:
A – 0.03%
B – 4%
B – 16%
G – 21%
How much carbon dioxide is in the inhaled air:
A – 0.03%
B – 4%
B – 16%
G – 21%
How much carbon dioxide is in exhaled air:
A – 0.03%
B – 4%
B – 16%
G – 21%
Where is the respiratory center located?
A – medulla oblongata
B – diencephalon
B – spinal cord
G – bark cerebral hemispheres?
What are the features of the humoral regulation of the respiratory center:
A – regulated by adrenal hormones
B - regulated by hormones thyroid gland
B – regulated mainly by the concentration of oxygen in the blood
D – is it regulated mainly by the concentration of carbon dioxide in the blood?
In what form is the bulk of oxygen transported in the blood?
A – blood plasma, in a dissolved state
B – in the form of myoglobin
B – in the form of oxyhemoglobin
G – in the form of carbohemoglobin?
Write down the numbers of the correct judgments:
1 – during inhalation, the intercostal muscles contract
2 – during inhalation, the ribs of the chest rise
3 – during exhalation, the diaphragm takes a flat shape
4 – during exhalation the muscles relax
5 - during inspiration, the pressure in the pulmonary vesicles is higher than atmospheric
6 – the diaphragm is not a respiratory muscle
7 – between the pulmonary and parietal pleura there is a pleural cavity common to both lungs.

1) List the structures that belong to the auxiliary apparatus of the organ of vision.

2) Write down the names of the parts of the eye through which light rays pass before they hit the retina.
3) Write down the definitions. ROD, CONE, RETINA, YELLOW SPOT BLIND SPOT.
4) Write recommendations for maintaining good vision.

1. Musculoskeletal... a person is made up of bones... and...

2. The skeleton serves... the body,... internal organs, with the help of it... bodies are carried out in space, it is also involved in... substances.
3. Shoulder, femur belong to... bones and consist of..., inside of which there is..., and two...
4. The walls of the cavities containing internal organs are formed... by bones, for example... a section of the skull, bones..., ribs; and the vertebrae and bones... the skulls consist of several different parts and refer to... bones.
5. Bone has a complex... composition and consists of 65–70%... substances that give..., and 30-35%... substances that give... and... bone.
6. Bone is mainly composed of... tissue, which is a type of... tissue, and is represented by... and... substance.
7. The compact substance is developed in the bones, performing the function... and..., and provides them with a large..., in special channels of this substance there are... vessels that feed the bone.
8. Spongy substance is formed by bone..., between which there is... bone marrow, forming cells...; cavity tubular bones filled with... bone marrow.
9. The outside of the bone is covered..., through which blood vessels... and... pass; due to it, bone growth occurs in...10. Between the bones of the skull and pelvis there are... connections, in this case the bones are connected by a layer of... tissue or..., in brain section and on the roof of the skull such formations are called...
11. Discontinuous connections of bones are called..., they allow a person to perform various...
12. The joint is formed between the surfaces of bones, covered..., on the outside they are enclosed in an articular..., strengthened..., inside which there is an articular..., reducing friction.
13. The skeleton of the head - ... - consists of ... and ... sections and is represented by ... bones that protect the head ... and sensory organs.
14. The skeleton of the body consists of the chest and..., represented by several sections:..., thoracic,..., sacral and...
15... has curves that act as shock absorbers, and is formed by vertebrae consisting of... and processes, the openings of the vertebral arches form a canal that protects... the brain.
16. The pectoral... consists of... pairs of ribs and..., protects the heart,..., serves to attach... muscles.
17. Belt upper limbs formed by pairs... and..., and free limb consists of... bones, forearm and...
18. The lower limbs consist of... bones, tibia and..., and the girdle of the lower limbs is represented by... bones that support... the pillar and internal organs.

To maintain life, it is necessary, on the one hand, to continuously absorb oxygen by the cells of a living organism and, on the other, to remove carbon dioxide formed as a result of oxidation processes. These two parallel processes constitute the essence of breathing.

In highly organized multicellular animals, respiration is provided by special organs - the lungs.

The human lungs consist of many individual small pulmonary vesicles of the alveoli with a diameter of 0.2 mm. But since their number is very large (about 700 million), the total surface is significant and amounts to 90 m 2.

The alveoli are densely intertwined with a network of the finest blood vessels - capillaries. The wall of the pulmonary vesicle and capillary together is only 0.004 mm thick.

Thus, the blood flowing through the capillaries of the lungs comes into extremely close contact with the air in the alveoli, where gas exchange occurs.

Atmospheric air enters the pulmonary vesicles, passing through the airways.

The respiratory tract itself begins with the so-called larynx at the place where the pharynx passes into the esophagus. The larynx is followed by the windpipe - the trachea with a diameter of about 20 mm, in the walls of which there are cartilaginous rings (Fig. 7).

Rice. 7. Upper breathing paths:
1 - nasal cavity: 2 - oral cavity; 3 - esophagus; 4 - larynx and windpipe (trachea); 5 - epiglottis

The trachea passes into the chest cavity, where it divides into two large bronchi - the right and left, on which the right and left lungs hang. Having entered the lung, the bronchus branches, its branches (medium and small bronchi) gradually become thinner and, finally, pass into the thinnest terminal branches - bronchioles, on which the alveoli sit.

The outside of the lungs is covered with a smooth, slightly moist membrane - the pleura. Exactly the same membrane covers the inside of the wall of the chest cavity, formed on the sides by the ribs and intercostal muscles, and below by the diaphragm or the pectoral muscle.

Normally, the lungs are not fused to the walls of the chest, they are only pressed tightly against them. This occurs because in the pleural cavities (between the pleural membranes of the lungs and chest walls), which are like narrow slits, there is no air. Inside the lungs, in the alveoli, there is always air that communicates with atmospheric pressure, so there is (on average) atmospheric pressure in the lungs. It presses the lungs against the walls of the chest with such force that the lungs cannot tear themselves away from them and passively follow them as the chest expands or contracts.

Blood, making a continuous circulation through the vessels of the alveoli, captures oxygen and releases carbon dioxide (CO 2). Therefore, for proper gas exchange it is necessary that the air in the lungs contains the required amount of oxygen and is not overfilled with CO 2 (carbon dioxide). This is ensured by constant partial renewal of air in the lungs. When you inhale, fresh atmospheric air enters the lungs, and when you exhale, the already used air is removed.

Breathing happens as follows. During inhalation, the force of the respiratory muscles expands the chest. The lungs, passively following the chest, suck in air through the respiratory tract. Then the chest, due to its elasticity, decreases in volume, the lungs compress and push excess air into the atmosphere. Exhalation occurs. During quiet breathing, 500 ml of air enters a person’s lungs during each breath. He exhales the same amount. This air is called breathing air. But if, after a normal inhalation, you take a deep breath, then another 1500-3000 ml of air will enter the lungs. It is called additional. In addition, when exhaling deeply after normal exhalation, up to 1000-2500 ml of so-called reserve air can be removed from the lungs. However, even after this, about 1000-1200 ml of residual air remains in the lungs.

The sum of the volume of respiratory, additional and reserve air is called the vital capacity of the lungs. It is measured using a special device - a spirometer. U different people The vital capacity of the lungs ranges from 3000 to 6000-7000 ml.

High vital capacity of the lungs has important for divers. The larger the lung capacity, the further underwater a diver can stay.

Breathing is regulated by special nerve cells- the so-called respiratory center, which is located next to the vasomotor center in the medulla oblongata.

The respiratory center is very sensitive to excess carbon dioxide in the blood. An increase in carbon dioxide in the blood irritates the respiratory center and increases breathing speed. Conversely, a sharp decrease in the carbon dioxide content in the blood or alveolar air causes a short-term cessation of breathing (apnea) for 1-1.5 minutes.

Breathing is under some control of the will. A healthy person can voluntarily hold his breath for 45-60 seconds.

The concept of gas exchange in the body(external and internal breathing). External breathing ensures gas exchange between the outside air and human blood, saturates the blood with oxygen and removes carbon dioxide from it. Internal respiration ensures the exchange of gases between the blood and tissues of the body.

The exchange of gases in the lungs and tissues occurs as a result of the difference in partial pressures of gases in the alveolar air, blood and tissues. Venous blood flowing to the lungs is poor in oxygen and rich in carbon dioxide. The partial pressure of oxygen in it (60-76 mm Hg) is significantly less than in the alveolar air (100-110 mm Hg), and oxygen freely passes from the alveoli into the blood. But the partial pressure of carbon dioxide in the venous blood (48 mm Hg) is higher than in the alveolar air (41.8 mm Hg), which forces carbon dioxide to leave the blood and pass into the alveoli, from where it is removed during exhalation . In the tissues of the body, this process occurs differently: oxygen from the blood enters the cells, and the blood is saturated with carbon dioxide, which is found in abundance in the tissues.

The relationship between the partial pressures of oxygen and carbon dioxide in atmospheric air, blood and body tissues can be seen from the table (the partial pressure values ​​are expressed in mmHg).

It should be added that a high percentage of carbon dioxide in the blood or tissues promotes the decomposition of hemoglobin oxide into hemoglobin and pure oxygen, A high content oxygen helps remove carbon dioxide from the blood through the lungs.

Features of breathing under water. We already know that a person cannot use the dissolved oxygen in water for breathing, since his lungs only need gaseous oxygen.

To ensure the vital functions of the body under water, it is necessary to systematically deliver the respiratory mixture to the lungs.

This can be done in three ways: through a breathing tube, using self-contained breathing apparatus and supplying air from the surface of the water to insulating devices (space suits, bathyscaphes, houses). These paths have their own characteristics. It has long been known that while underwater you can breathe through a snorkel at a depth of no more than 1 m.

At greater depths, the respiratory muscles cannot overcome the additional resistance of the water column, which presses on chest. Therefore, for swimming underwater, breathing tubes no longer than 0.4 m are used.

But even with such a tube, the breathing resistance is still quite high, moreover, the air entering the inhalation is somewhat depleted in oxygen and has a slight excess of carbon dioxide, which leads to excitation of the respiratory center, expressed in moderate shortness of breath (the respiratory rate increases by 5-7 breaths per minute).

To ensure normal breathing at depth, it is necessary to supply air to the lungs at a pressure that would correspond to the pressure at a given depth and could balance the external pressure of water on the chest.

In an oxygen suit, the breathing mixture is compressed to the required degree before entering the lungs; in a breathing bag, it is compressed directly by ambient pressure.

In a self-contained compressed air breathing apparatus, this function is performed by a special mechanism. In this case, it is important to observe certain limits of breathing resistance, since a significant amount of it has a negative effect on the human cardiovascular system, causes fatigue of the respiratory muscles, as a result of which the body is not able to maintain the necessary breathing pattern.

In lung-automatic devices, the breathing resistance is still quite high. Its magnitude is estimated because the effort of the respiratory muscles, which creates a vacuum in the lungs, respiratory tract, inhalation tube and in the submembrane cavity of the pulmonary valve. In conditions atmospheric pressure, as well as in the vertical position of a scuba diver in water, when the lung demand valve is at the same level with the “center” of the lungs, the breathing resistance during inhalation is about 50 mm of water. Art. During horizontal swimming with scuba diving, the lung demand valve of which is located behind the back on cylinders, the difference between the water pressure on the lung demand valve membrane and on the scuba diver’s chest is about 300 mm of water. Art.

Therefore, the inhalation resistance reaches 350 mm of water. Art. To reduce breathing resistance, the second stage of reduction in new types of scuba gear is placed in the mouthpiece.

In ventilated equipment, where air is supplied through a hose from the surface, it is compressed using special diving pumps or compressors, and the degree of compression must be proportional to the depth of immersion. The amount of pressure in this case is controlled by a pressure gauge installed between the pump and the diving hose.