Functions of the lungs. Human lungs: structure, functions

While a person is alive, he is breathing. What is breathing? These are processes that continuously supply all organs and tissues with oxygen and remove from the body carbon dioxide, formed as a result of the operation of the exchange system. These vital processes are performed by the respiratory system, which directly interacts with the cardiovascular system. To understand how gas exchange takes place in the human body, it is necessary to study the structure and functions of the lungs.

Why does man breathe?

The only way to get oxygen is breathing. For a long time to detain it does not work, because the body requires another portion. Why do we need oxygen? Without it, there will be no metabolism, work the brain and all other human organs. With the participation of oxygen, nutrients are broken down, energy is released, and each cell is enriched with them. Breathing is usually called gas exchange. And this is true. After all, the peculiarities of the respiratory system consist in taking oxygen from the air that gets into the body, and withdrawing carbon dioxide.

What are the lungs of a person?

Their anatomy is rather complicated and variable. This organ is paired. The place of its location is the thoracic cavity. The lungs adhere to the heart on both sides - right and left. Nature has ensured that both these important organs are protected from squeezing, blows, etc. The front for damage is the thorax, behind - the spinal column, and on the sides - the ribs.

The lungs are literally permeated with hundreds of branches of bronchi, with alveoli, the size of a pinhead located at their ends. They are in the body of a healthy person, there are up to 300 million pieces. Alveoli perform an important role: they supply blood vessels with oxygen and, having a branched system, are able to provide a large area for gas exchange. Imagine only: they can cover the entire surface of the tennis court!

In appearance, the lungs resemble semi-cones, whose bases adjoin the diaphragm, and the tips with rounded ends protrude 2-3 cm above the clavicle. A rather peculiar organ is the lungs of man. The anatomy of the right and left lobes is different. So, the first is slightly larger in volume than the second, while it is somewhat shorter and wider. Each half of the organ is covered with a pleura consisting of two sheets: one is spliced with the thorax, the other - with the surface of the lung. In the external pleura contains glandular cells, due to which a pleural cavity is produced by the liquid.

The inner surface of each lung has a groove, which is called the gate. They include bronchi, the base of which is a branching tree, and the pulmonary artery, and a pair of pulmonary veins emerges.

The lungs of man. Their functions

Of course, in the human body there are no secondary organs. Important in providing life of a person are the lungs. What kind of work do they do?

• The main functions of the lungs are to carry out the respiratory process. A person lives while breathing. If the oxygen supply to the body stops, death will come.
• The work of the lungs is to remove carbon dioxide, so that the body maintains an acid-base balance. Through these organs a person gets rid of volatile substances: alcohol, ammonia, acetone, chloroform, ether.

• The functions of the lungs are not limited to this. The paired organ is still involved in purifying the blood that comes into contact with the air. As a result, there is an interesting chemical reaction. The molecules of oxygen in the air and the molecules of carbon dioxide in the dirty blood are exchanged, that is, oxygen replaces carbon dioxide.
• Different functions of the lungs allow them to participate in the water exchange that takes place in the body. Up to 20% of the liquid is discharged through them.
• Lungs are active participants in the process of heat regulation. They give into the atmosphere 10% of the heat with the exhalation of air.
• Regulation of blood clotting can not do without participation in this process of lungs.

How does the lungs work?

The functions of the lungs are to transfer the oxygen contained in the air to the blood, use it, and remove carbon dioxide from the body. Lungs - fairly large soft organs with a spongy tissue. The inhaled air enters the air sacs. They are separated by thin walls with capillaries.

Between the blood and the air, only small cells. Therefore, for inhaled gases, thin walls do not constitute obstacles, which promotes good passability through them. In this case, the functions of the lungs of a person consist in using the necessary gases and removing unnecessary gases. The tissues of the lungs are very elastic. When inhaled, the chest widens and the lungs expand in volume.

The respiratory throat, represented by the nose, pharynx, larynx, trachea, looks like a tube 10-15 cm long, divided into two parts, called bronchi. Air, passing through them, enters the air sacs. And when you exhale, there is a reduction in lung volume, a reduction in the size of the chest, a partial closure of the pulmonary valve, which allows the air to exit again. This is how the lungs work.

The structure and functions of these are such that the capacity of this organ is measured by the amount of inhaled and exhaled air. So, in men it is equal to seven pints, for women - five. Lungs are never empty. The air left after exhalation is called residual air. When inhaled, it mixes with fresh air. Therefore, breathing is a conscious and simultaneously unconscious process that happens all the time. A man breathes when he sleeps, but he does not think about it. At the same time, if desired, you can briefly interrupt the breathing. For example, while under water.

Interesting facts about the functioning of the lungs

They are able to pump 10 thousand liters of air per day. But not always it is crystal clear. Along with oxygen, dust, many microbes and foreign particles enter our body. Therefore, the lungs function Protection against all unwanted impurities in the air.

The walls of the bronchi have many tiny villi. They are needed in order to detain microbes and dust. And the mucus that is produced by the cells of the walls of the respiratory tract, lubricates these villi, and then outwardly when coughing.

Structure of the respiratory system

It consists of organs and tissues that fully provide ventilation and breathing. In the implementation of gas exchange - the main link in the metabolism - the respiratory system functions. The latter is responsible only for pulmonary (external) breathing. It includes:

1. Airways, consisting of the nose and its cavity, larynx, trachea, bronchi.

The nose and its cavity are heated, moistened and filtered by inhaled air. Its purification is achieved due to numerous hard hairs and goblet cells with cilia.

The larynx lies between the root of the tongue and the trachea. Its cavity is separated by a mucosa in the form of two folds. In the middle they are not fully fused. A gap between them is called a voice gap.

The trachea originates from the larynx. In the chest, it is divided into bronchi: the right and left.

2. Lungs with densely branched vessels, bronchioles and alveolar sacs. They begin the gradual division of the main bronchi into small tubes, called bronchioles. Of these, the smallest structural elements of the lung are composed of lobules.

In the pulmonary artery, the blood carries the right ventricle of the heart. It is divided into left and right. The branching of the arteries follows the bronchi, braiding the alveoli and forming small capillaries.

3. The musculoskeletal system, thanks to which the person is not limited in respiratory movements.

These are the ribs, muscles, diaphragm. They monitor the integrity of the airways and conserve them during various postures and movements of the body. Muscles, contracting and relaxing, contribute to a change in the volume of the chest. The diaphragm is designed to separate the thoracic cavity from the abdominal cavity. It is the main muscle involved in normal inspiration.

The person breathes a nose. Then the air passes through the airways and enters the lungs of a person whose structure and functions ensure the further work of the respiratory system. This is purely a physiological factor. This breath is called nasal. In the cavity of this body there is heating, moistening and purifying the air. If the mucous membrane of the nose is irritated, the person sneezes, and protective mucus begins to emerge. Nasal breathing can be difficult. Then the air through the mouth falls into the throat. About such a breath they say that it is oral and, in fact, is pathological. In this case, the functions of the nasal cavity are disrupted, which causes various diseases of the respiratory tract.

From the pharynx, air is directed to the larynx, which performs other functions besides carrying oxygen further into the respiratory tract, in particular, reflexogenic. If there is irritation of this organ, a cough or spasm appears. In addition, the larynx is involved in sound formation. This is important for any person, since his communication with other people is through speech. Trachea and bronchi continue to heat and humidify the air, but this is not their main function. By performing a certain work, they regulate the volume of inhaled air.

Respiratory system. Functions

The air that surrounds us contains oxygen in its composition, which can penetrate into our body and through the skin. But its quantity is not enough to support life. For this, there is a respiratory system. Transportation of necessary substances and gases is carried out by the circulatory system. The structure of the respiratory system is such that it is able to supply the body with oxygen and removes carbon dioxide from it. It performs the following functions:

• Regulates, conducts, moisturizes and degreases air, removes dust particles.
• Protects the respiratory tract from ingesting food.
• Conducts air into the trachea from the larynx.
• Improves gas exchange between the lungs and blood.
• Carries out transportation of venous blood into the lungs.
• Saturates oxygen and bleeds carbon dioxide.
• Performs a protective function.
• Delays and resolves blood clots, particles of foreign origin, emboli.
• Executes the exchange of necessary substances.

Interesting is the fact that with age, the functionality of the respiratory system is limited. The level of ventilation of the lungs and the work of breathing decreases. The causes of such disorders can be various changes in the bones and muscles of a person. As a result, the shape of the chest changes , and its mobility decreases. This leads to a decrease in the capacity of the respiratory system.

The phases of breathing

At inspiration, oxygen from the alveoli of the lung enters the blood, namely into the erythrocytes. Hence, on the contrary, carbon dioxide passes into the air in which oxygen was contained. From the time of entry and until the release of air from the lungs, its pressure in the organ increases, which stimulates the diffusion of gases.

When exhaling in the alveoli of the lungs, a pressure is created that exceeds the atmospheric pressure. The diffusion of gases begins to take place more actively: carbon dioxide and oxygen.

Every time after exhalation a pause is created. This is because there is no diffusion of gases, since the pressure of air remaining in the lungs is insignificant, much lower than atmospheric pressure.

As long as I breathe, I live. The process of breathing

• To the child in the womb, oxygen flows through her blood, so the baby's lungs do not participate in the process, they are filled with fluid. When the baby is born and takes its first breath, the lungs begin to work. The structure and functions of the respiratory system are such that they are able to provide the human body with oxygen and remove carbon dioxide.
• The signals about the amount of oxygen required in a specific time interval provide the respiratory center, which is located in the brain. So, during sleep, oxygen is required much less than during working hours.
• The volume of air entering the lungs is regulated by messages sent by the brain.

• During the arrival of this signal, the diaphragm spreads, which leads to the stretching of the chest. This maximizes the volume that the lungs occupy during expansion during inspiration.
• During exhalation, the diaphragm and intercostal muscles relax, the volume of the chest decreases. This leads to expulsion of air from the lungs.

Types of breathing

• The clueless. When a person hunches, his shoulders are raised, and the stomach is compressed. This indicates an inadequate intake of oxygen into the body.
• Chest breathing. It is characterized by the expansion of the chest due to the intercostal muscles. Such functions of the respiratory system contribute to saturation of the body with oxygen. This method is purely physiologically suitable for pregnant women.
• Deep breathing fills the lower parts of the air with air. Most often, both men and women breathe. This method is convenient during exercise by physical activity.

No wonder they say that breathing is a mirror of mental health. So, psychiatrist Lowen has noticed an amazing relationship between the nature and type of emotional disorder of a person. In people prone to schizophrenia, the upper part of the chest is involved in breathing. A person with a neurotic type of character breathes more belly. Usually people use mixed breathing, in which both the thorax and the diaphragm participate.

Light Smoking People

Smoking causes a severe blow to the organs. Tobacco smoke contains tar, nicotine and hydrogen cyanide. These harmful substances have the ability to settle on the lung tissue, resulting in death of the epithelium of the organ. The lungs of a healthy person are not affected by such processes.

Smoking people have lungs dirty gray or black due to the accumulation of a huge number of dead cells. But this is not all the negative aspects. Lung functions are significantly reduced. Negative processes that lead to inflammation begin. As a consequence, a person suffers from chronic obstructive pulmonary diseases that contribute to the development of respiratory failure. It, in turn, causes numerous violations that occur due to a lack of oxygen in the tissues of the body.

Social advertising constantly shows clips, pictures with the difference between the lungs of a healthy and smoking person. And many people who have never taken a cigarette in their hands, sigh with relief. But do not be so reassuring yourself, believing that the eerie sight, which are the lungs of a smoker, has nothing to do with you. Interestingly, there is no special external difference at first glance. Neither X-ray, nor ordinary fluorography will show, the person who smokes or not. Moreover, no pathologist will be able to determine with absolute certainty whether a person has a predilection for smoking during life until he discovers typical signs: bronchial condition, yellowing of fingers and so on. Why is that? It turns out that harmful substances that are in the gassed air of cities, getting into our body, just like tobacco smoke, get into the lungs ...

The structure and functions of this body are designed to protect the body. It is known that toxins destroy the lung tissue, which subsequently, due to the accumulation of dead cells, acquires a dark color.

What is the essence of advertising? Just on the posters with comparative inscriptions depict the organs of an adult and ... an infant.

Interesting information about breathing and respiratory system

• The lungs have the size of a human palm.
• The volume of the paired organ is 5 liters. But it is not fully used. To ensure normal breathing, 0.5 liters is enough. The volume of residual air is one and a half liters. If you count, then exactly three liters of air volume is always in reserve.
• The older the person, the less his breathing. For one minute the newborn inhales-exhales thirty-five times, the adolescent - twenty, the adult - fifteen times.
• For one hour a person makes a thousand breaths, for a day - twenty-six thousand, for a year - nine million. And men and women do not breathe the same way. In one year, the first do 670 million breaths-exhalations, and the second - 746.
• For one minute a person is vital to get eight and a half liters of air volume.

Proceeding from all above-stated, we do a conclusion: behind lungs it is necessary to watch. If you are in doubt about your respiratory system, consult a doctor.