What about the respiratory system. The structure of the respiratory system What organs of the respiratory tract

Respiratory system A person provides gas exchange between the atmospheric air and the lungs, as a result of which oxygen from the lungs enters the blood and is transported by the blood to the tissues of the body, and carbon dioxide is transported from the tissues in the opposite direction. At rest, the tissues of an adult human body consume approximately 0.3 liters of oxygen per minute and produce a slightly smaller amount of carbon dioxide in them. The ratio of the amount of CO2 formed in its tissues to the amount of CO2 consumed by the body is called the respiratory coefficient, the value of which under normal conditions is 0.9. maintenance normal level gas homeostasis of 02 and CO2 of the body in accordance with the rate of tissue metabolism (respiration) is the main function of the respiratory system of the human body.

This system consists of a single complex of bone, cartilage, connective and muscle tissues. chest, respiratory tract(air-bearing section of the lungs), which ensure the movement of air between the external environment and the air space of the alveoli, as well as lung tissue (respiratory section of the lungs), which has high elasticity and extensibility. The respiratory system includes its own nervous apparatus that controls the respiratory muscles of the chest, sensory and motor fibers of neurons of the autonomic nervous system, which have terminals in the tissues of the respiratory organs. The place of gas exchange between the human body and the external environment is the alveoli of the lungs, the total area of ​​which reaches an average of 100 m2.

Alveoli (about 3.108) are located at the end of the small airways of the lungs, have a diameter of approximately 0.3 mm and are in close contact with the pulmonary capillaries. Blood circulation between the cells of the tissues of the human body, consuming 02 and producing CO2, and the lungs, where these gases are exchanged with atmospheric air, is carried out by the circulatory system.

Functions of the respiratory system. In the human body, the respiratory system performs respiratory and non-respiratory functions. The respiratory function of the system maintains the gas homeostasis of the internal environment of the body in accordance with the level of metabolism of its tissues. With the inhaled air, dust microparticles enter the lungs, which are retained by the mucous membrane of the respiratory tract and then removed from the lungs with the help of protective reflexes (coughing, sneezing) and mucociliary clearance mechanisms (protective function).

The non-respiratory functions of the system are due to processes such as synthesis (surfactant, heparin, leukotrienes, prostaglandins), activation (angiotensin II) and inactivation (serotonin, prostaglandins, norepinephrine) biologically active substances, with the participation of alveolocytes, mast cells and the endothelium of the capillaries of the lungs (metabolic function). The epithelium of the mucous membrane of the respiratory tract contains immunocompetent cells (T- and B-lymphocytes, macrophages) and mast cells(synthesis of histamine), providing a protective function of the body. Through the lungs, water vapor and molecules of volatile substances are removed from the body with exhaled air (excretory function), as well as an insignificant part of the heat from the body (thermoregulatory function). The respiratory muscles of the chest are involved in maintaining the position of the body in space (postural-tonic function). Finally, the nervous apparatus of the respiratory system, the muscles of the glottis and upper respiratory tract, as well as the muscles of the chest, are involved in human speech activity (speech production function). The main respiratory function of the respiratory system is realized in the processes of external respiration, which are the exchange of gases (02, CO2 and N2) between the alveoli and the external environment, the diffusion of gases (02 and CO2) between the alveoli of the lungs and blood (gas exchange). Along with external breathing in the body, respiratory gases are transported by blood, as well as gas exchange of 02 and CO2 between blood and tissues, which is often called internal (tissue) respiration.

Scientists have established interesting fact. The air that enters the human respiratory organs conditionally forms two streams, one of which passes into the left side of the nose and enters the left lung, the second stream enters the right side of the nose and enters the right lung.

Also, studies have shown that in the artery of the human brain there is also a separation into two streams of air received. The breathing process must be correct, which is important for normal life. Therefore, it is necessary to know about the structure of the human respiratory system and respiratory organs.

The human respiratory apparatus includes the trachea, lungs, bronchi, lymphatics, and vascular system. They also include nervous system and respiratory muscles, pleura. The human respiratory system includes the upper and lower respiratory tract. Upper respiratory tract: nose, pharynx, oral cavity. Lower respiratory tract: trachea, larynx and bronchi.

The airways are necessary for the entry and removal of air from the lungs. The most important organ of the entire respiratory system is the lungs, between which the heart is located.

Respiratory system

nasal cavity

The mucous membrane prevents too dry air from entering the body and provides it with the necessary moisture. In addition, its blood vessels maintain the optimal temperature in the nasal cavity, and the folds of the inner wall retain and warm the inhaled air.

Oral cavity

The function of the oral cavity in the process of breathing is insignificant, since the nostrils are much better adapted for this purpose. Nevertheless, it serves as an inlet and outlet for air in cases where there is a great need to saturate the lungs with oxygen. For example, when we make great physical efforts or when the nostrils are clogged due to an injury or a cold.

Oral cavity takes part in speech formation, since the tongue and teeth articulate the sounds produced by the vocal cords in the larynx.

Trachea

Pharynx

Larynx

Bronchi

The bronchi that enter the lobes of the lungs are called the lobar bronchi, and there are three in the right lung and two in the left. Further, the lobar bronchi continue to branch and narrow, dividing into segmental bronchi, and, finally, turn into tubes with a diameter of less than 1 mm - bronchioles.

Bronchioles distribute oxygen with their endings, pulmonary alveoli, a kind of bubbles in which gas exchange takes place, that is, the exchange of carbon dioxide for oxygen.

Lungs -

The lungs include the bronchial tree, which is formed by bifurcation of the trachea. The bronchi, in turn, are divided into thinner ones, thus forming segmental bronchi. The bronchial tree ends with very small sacs. These sacs are many interconnected alveoli. Alveoli provide gas exchange in the respiratory system. The bronchi are covered with epithelium, which in its structure resembles cilia. Cilia remove mucus to the pharyngeal region. Promotion is promoted by coughing. The bronchi have a mucous membrane.

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

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

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

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

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

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

Types of breathing

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

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

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

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

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

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

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

Breath types

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

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

Breathing happens:

• deep and superficial;
• frequent and rare.

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

The system and structure of the respiratory system

The respiratory system includes:

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

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

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

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

Breathing process

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

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

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

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

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

Functions of the respiratory system

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

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

Breathing regulation

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

Nervous regulation has a reflex effect on breathing. The collapse of the pulmonary alveoli, which occurs during exhalation, reflexively causes inspiration, and the expansion of the alveoli reflexively causes exhalation. Its activity depends on the concentration of carbon dioxide (CO2) in the blood and on nerve impulses coming from receptors of various internal organs and skin.Hot or cold stimulus ( sensory system) 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 muscular work, oxidation processes are enhanced. Consequently, more carbon dioxide is released into the blood. When blood with an excess of carbon dioxide reaches the respiratory center and begins to irritate it, the activity of the center increases. The person begins to breathe deeply. As a result, excess carbon dioxide is removed, and the lack of oxygen is replenished.

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

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

With problems with external respiration, certain

Vital capacity of the lungs

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

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

Breath and physical exercise

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

Devices for the study of respiratory parameters

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

OUR LUNGS LOVE:

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

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

OUR LUNGS DON'T LIKE:

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

2. Polluted air(car exhaust, dust, polluted air, smoke, vodka fumes, carbon monoxide All these components have an adverse effect on the body. Hemoglobin molecules that have captured carbon monoxide are permanently deprived of the ability to carry 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 involved in metabolism and interfere with nervous and humoral regulation, disrupting both. In addition, tobacco smoke substances irritate the mucous membrane of the respiratory tract, which leads to an increase in the mucus secreted by it).

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

Line UMK Ponomareva (5-9)

Biology

The structure of the human respiratory system

The respiratory system is a set of organs that ensure the supply of oxygen from the surrounding air to the respiratory tract and carry out gas exchange, i.e. the entry of oxygen into the bloodstream and the removal of carbon dioxide from the bloodstream back into the atmosphere. However, the respiratory system is not only providing the body with oxygen - it is also human speech, and the capture of various odors, and heat transfer.

Organs of the human respiratory system conditionally divided into Airways, or conductors through which the air mixture enters the lungs, and lung tissue, or alveoli.

The respiratory tract is conventionally divided into upper and lower according to the level of attachment of the esophagus. The top ones are:

• nose and paranasal sinuses
• oropharynx
• larynx

• trachea
• main bronchi
• bronchi of the following orders
• terminal bronchioles.

The nasal cavity is the first frontier when air enters the body. Numerous hairs located on the nasal mucosa stand in the way of dust particles and purify the passing air. The nasal conchas are represented by a well-perfused mucosa and, passing through the tortuous nasal conchas, the air is not only cleansed, but also warmed.

Also, the nose is the organ by which we enjoy the aroma of freshly baked bread, or we can pinpoint the location of a public toilet. And all because sensitive olfactory receptors are located on the mucous membrane of the superior nasal concha. Their quantity and sensitivity are genetically programmed, thanks to which perfumers create memorable perfume aromas.

Passing through the oropharynx, air enters the larynx. How is it that food and air pass through the same parts of the body and do not mix? When swallowing, the epiglottis covers the airways, and food enters the esophagus. If the epiglottis is damaged, a person may choke. Inhalation of food requires immediate attention and can even lead to death.

The larynx is made up of cartilage and ligaments. The cartilages of the larynx are visible to the naked eye. The largest of the cartilages of the larynx is the thyroid cartilage. Its structure depends on sex hormones and in men it strongly moves forward, forming adam's apple, or Adam's apple. It is the cartilages of the larynx that serve as a guide for doctors when performing a tracheotomy or conicotomy - operations that are performed when foreign body or a tumor blocks the airway, and in the usual way a person cannot breathe.

Further, the vocal cords get in the way of air. It is by passing through the glottis and causing the stretched vocal cords to tremble that not only the function of speech, but also singing is available to a person. Some unique singers can make vocal cords tremble at 1000 decibels and explode crystal glasses with the force of their voices.
(in Russia, Svetlana Feodulova, a participant in the Voice-2 show, has the widest voice range of five octaves).

The trachea has a structure cartilaginous semirings. The anterior cartilaginous part provides unhindered passage of air due to the fact that the trachea does not collapse. The esophagus is adjacent to the trachea, and the soft part of the trachea does not delay the passage of food through the esophagus.

Further, the air through the bronchi and bronchioles, lined with ciliated epithelium, reaches the final section of the lungs - alveoli. Lung tissue, or alveoli - final, or terminal sections of the tracheobronchial tree, similar to blindly ending bags.

Many alveoli form the lungs. The lungs are a paired organ. Nature took care of her negligent children, and created some important organs - lungs and kidneys - in duplicate. A person can live with one lung. The lungs are located under the reliable protection of the frame of strong ribs, sternum and spine.

The textbook complies with the Federal State Educational Standard for Basic General Education, is recommended by the Ministry of Education and Science of the Russian Federation and is included in the Federal List of Textbooks. The textbook is addressed to students of the 9th grade and is included in the educational and methodological complex "Living Organism", built on a linear principle.

Interestingly, the lungs are devoid of muscle tissue and cannot breathe on their own. Respiratory movements are provided by the work of the muscles of the diaphragm and intercostal muscles.

A person makes respiratory movements due to the complex interaction of various groups of intercostal muscles, abdominal muscles during deep breathing, and the most powerful muscle involved in breathing is diaphragm.

The experiment with the Donders model described on page 177 of the textbook will help to visualize the work of the respiratory muscles.

Lungs and chest lined pleura. The pleura that lines the lungs is called pulmonary, or visceral. And the one that covers the ribs - parietal, or parietal. The structure of the respiratory system provides the necessary gas exchange.

When inhaling, the muscles stretch the lung tissue, like a skilled musician of a button accordion fur, and the air mixture of atmospheric air, consisting of 21% oxygen, 79% nitrogen and 0.03% carbon dioxide, enters through the respiratory tract to the final section, where the alveoli, braided with a thin network of capillaries, are ready to receive oxygen and give off the waste carbon dioxide from the human body. The composition of the exhaled air is characterized by a significantly higher content of carbon dioxide - 4%.

To imagine the scale of gas exchange, just think that the area of ​​all alveoli human body about the size of a volleyball court.

To prevent the alveoli from sticking together, their surface is lined with surfactant- a special lubricant containing lipid complexes.

The terminal sections of the lungs are densely braided with capillaries and the wall of the blood vessels is in close contact with the wall of the alveoli, which allows the oxygen contained in the alveoli to enter the blood through a difference in concentration, without the participation of carriers, by passive diffusion.

If you remember the basics of chemistry, and specifically - the topic solubility of gases in liquids, especially meticulous ones can say: “What nonsense, because the solubility of gases decreases with increasing temperature, and here you are telling that oxygen dissolves perfectly in a warm, almost hot - about 38-39 ° C, salty liquid.”
And they are right, but they forget that an erythrocyte contains an invader hemoglobin, one molecule of which can attach 8 oxygen atoms and transport them to the tissues!

In the capillaries, oxygen binds to a carrier protein on red blood cells, and oxygenated arterial blood returns to the heart through the pulmonary veins.
Oxygen is involved in the processes of oxidation, and as a result, the cell receives the energy necessary for life.

Respiration and gas exchange are the most important functions of the respiratory system, but far from the only ones. The respiratory system ensures the maintenance of heat balance due to the evaporation of water during breathing. A careful observer noticed that in hot weather a person begins to breathe more often. In humans, however, this mechanism does not work as efficiently as in some animals, such as dogs.

Hormonal function through the synthesis of important neurotransmitters(serotonin, dopamine, adrenaline) provide pulmonary neuroendocrine cells ( PNE-pulmonary neuroendocrine cells). Also, arachidonic acid and peptides are synthesized in the lungs.

Biology. Grade 9 Textbook

A biology textbook for grade 9 will help you get an idea of ​​the structure of living matter, its most general laws, the diversity of life and the history of its development on Earth. When working, you will need your life experience, as well as knowledge of biology acquired in grades 5-8.

The respiratory center is located in the brain stem, which consists of several disparate groups of neurons. There are three main groups of neurons:

• dorsal group- the main source of impulses that provide a constant rhythm of breathing;
• ventral group- controls the level of ventilation of the lungs and can stimulate inhalation or exhalation, depending on the moment of excitation. It is this group of neurons that controls the abdominal and abdominal muscles for deep breathing;
• pneumotaxic center - thanks to its work, there is a smooth change from exhalation to inhalation.

To fully provide the body with oxygen, the nervous system regulates the rate of ventilation of the lungs through a change in the rhythm and depth of breathing. Thanks to well-established regulation, even active physical activity has practically no effect on the concentration of oxygen and carbon dioxide in arterial blood.

In the regulation of respiration are involved:

• carotid sinus chemoreceptors, sensitive to the content of gases O 2 and CO 2 in the blood. The receptors are located in the inner carotid artery at the level of the upper edge of the thyroid cartilage;
• lung stretch receptors located in the smooth muscles of the bronchi and bronchioles;
• inspiratory neurons located in the medulla oblongata and the pons (divided into early and late).

Physiologists suggested that individual neurons unite into neural networks to regulate the sequence of inhalation-exhalation phases, register individual types of neurons with their information flow and change the rhythm and depth of breathing in accordance with this flow.

The respiratory center located in the medulla oblongata controls the level of tension in the blood gases and regulates the ventilation of the lungs with the help of respiratory movements so that the concentration of oxygen and carbon dioxide is optimal. Regulation is carried out using a feedback mechanism.

You can read about the regulation of breathing using the protective mechanisms of coughing and sneezing on page 178 of the textbook.

Respiration is the process of exchanging gases such as oxygen and carbon between the internal environment of a person and the outside world. Human breathing is a complexly regulated act of joint work of nerves and muscles. Them harmonious work ensures the implementation of inspiration - the supply of oxygen to the body, and exhalation - the removal of carbon dioxide into the environment.

The respiratory apparatus has a complex structure and includes: organs of the human respiratory system, muscles responsible for the acts of inhalation and exhalation, nerves that regulate the entire process of air exchange, as well as blood vessels.

Vessels are of particular importance for the implementation of breathing. Blood through the veins enters the lung tissue, where the exchange of gases takes place: oxygen enters, and carbon dioxide leaves. The return of oxygenated blood is carried out through the arteries, which transport it to the organs. Without the process of tissue oxygenation, breathing would have no meaning.

Respiratory function is assessed by pulmonologists. Important indicators for this are:

1. Bronchial lumen width.
2. Breathing volume.
3. Inspiratory and expiratory reserve volumes.

A change in at least one of these indicators leads to a deterioration in well-being and is an important signal for additional diagnosis and treatment.

In addition, there are secondary functions that the breath performs. It:

1. Local regulation of the breathing process, due to which the vessels are adapted to ventilation.
2. Synthesis of various biologically active substances that constrict and expand blood vessels as needed.
3. Filtration, which is responsible for the resorption and decay of foreign particles, and even blood clots in small vessels.
4. Deposition of cells of the lymphatic and hematopoietic systems.

Stages of the breathing process

Thanks to nature, which invented such a unique structure and functions of the respiratory organs, it is possible to carry out such a process as air exchange. Physiologically, it has several stages, which, in turn, are regulated by the central nervous system, and only thanks to this they work like clockwork.

So, as a result of many years of research, scientists have identified the following stages, which collectively organize breathing. It:

1. External respiration - the delivery of air from the external environment to the alveoli. All organs of the human respiratory system take an active part in this.
2. Delivery of oxygen to organs and tissues by diffusion, as a result of this physical process, tissue oxygenation occurs.
3. Respiration of cells and tissues. In other words, the oxidation of organic substances in cells with the release of energy and carbon dioxide. It is easy to understand that without oxygen, oxidation is impossible.

The value of breathing for a person

Knowing the structure and functions of the human respiratory system, it is difficult to overestimate the importance of such a process as breathing.

In addition, thanks to him, the exchange of gases between the internal and external environment of the human body is carried out. The respiratory system is involved:

1. In thermoregulation, that is, it cools the body when elevated temperature air.
2. In the function of releasing random foreign substances such as dust, microorganisms and mineral salts, or ions.
3. In the creation of speech sounds, which is extremely important for the social sphere of man.
4. In the sense of smell.

General characteristics of the respiratory system

The most important indicator of human viability can be called breath. A person can do without water and food for some time, but life is impossible without air. Breathing is the link between a person and the environment. If the air flow is obstructed, then respiratory organs I am a person and the heart begins to work in an enhanced mode, which provides the necessary amount of oxygen for breathing. The human respiratory and respiratory system is capable of adapt to environmental conditions.

Scientists have established an interesting fact. The air that enters respiratory system of a person, conditionally forms two streams, one of which passes into the left side of the nose and penetrates into left lung, the second stream penetrates the right side of the nose and feeds into right lung.

Also, studies have shown that in the artery of the human brain there is also a separation into two streams of air received. Process breathing must be correct, which is important for normal life. Therefore, it is necessary to know about the structure of the human respiratory system and respiratory organs.

Breathe-helping machine human includes trachea, lungs, bronchi, lymphatics, and vascular system. They also include the nervous system and respiratory muscles, the pleura. The human respiratory system includes the upper and lower respiratory tract. Upper respiratory tract: nose, pharynx, oral cavity. Lower respiratory tract: trachea, larynx and bronchi.

The airways are necessary for the entry and removal of air from the lungs. The most important organ of the entire respiratory system is lungs between which the heart is located.

Respiratory system

Lungs- the main organs of respiration. They are cone shaped. The lungs are located in the chest area, located on either side of the heart. The main function of the lungs is gas exchange, which occurs with the help of the alveoli. The lungs receive blood from the veins through the pulmonary arteries. Air penetrates through the respiratory tract, enriching the respiratory organs with the necessary oxygen. Cells need to be supplied with oxygen in order for the process to take place. regeneration, and nutrients from the blood needed by the body. Covers the lungs - the pleura, consisting of two petals, separated by a cavity (pleural cavity).

The lungs include the bronchial tree, which is formed by bifurcation trachea. The bronchi, in turn, are divided into thinner ones, thus forming segmental bronchi. bronchial tree ends with very small pouches. These sacs are many interconnected alveoli. Alveoli provide gas exchange respiratory system. The bronchi are covered with epithelium, which in its structure resembles cilia. Cilia remove mucus to the pharyngeal region. Promotion is promoted by coughing. The bronchi have a mucous membrane.

Trachea is a tube that connects the larynx and bronchi. The trachea is about 12-15 see Trachea, in contrast to the lungs - an unpaired organ. The main function of the trachea is to carry air into and out of the lungs. The trachea is located between the sixth vertebra of the neck and the fifth vertebra of the thoracic region. In the end trachea bifurcates into two bronchi. The bifurcation of the trachea is called a bifurcation. At the beginning of the trachea, the thyroid gland adjoins it. On the back of the trachea is the esophagus. The trachea is covered by a mucous membrane, which is the basis, and it is also covered by muscular-cartilaginous tissue, a fibrous structure. The trachea is made up of 18-20 rings of cartilage, thanks to which the trachea is flexible.

Larynx- a respiratory organ that connects the trachea and pharynx. The voice box is located in the larynx. The larynx is in the area 4-6 vertebrae of the neck and with the help of ligaments attached to the hyoid bone. The beginning of the larynx is in the pharynx, and the end is a bifurcation into two tracheas. The thyroid, cricoid, and epiglottic cartilages make up the larynx. These are large unpaired cartilages. It is also formed by small paired cartilages: horn-shaped, wedge-shaped, arytenoid. The connection of the joints is provided by ligaments and joints. Between the cartilages are membranes that also perform the function of connection.

Pharynx is a tube that originates in the nasal cavity. The pharynx crosses the digestive and respiratory tracts. The pharynx can be called the link between the nasal cavity and the oral cavity, and the pharynx also connects the larynx and esophagus. The pharynx is located between the base of the skull and 5-7 neck vertebrae. The nasal cavity is the initial section of the respiratory system. Consists of the external nose and nasal passages. The function of the nasal cavity is to filter the air, as well as to purify and moisten it. Oral cavity This is the second way air enters the human respiratory system. The oral cavity has two sections: posterior and anterior. The anterior section is also called the vestibule of the mouth.