Structure and operation of respiratory organs

The human respiratory system is composed, first, of pneumatic ways that only make the air clean and warming it, but do not themselves participate in gas exchange (nose, throat, larynx, trachea, bronchi), and, second, from the respiratory organs (lungs), in which flowing from the right ventricle of the heart the blood is closely related to the air.
Airway lined from inside the delicate mucous membranes, which laid the mass of tiny glands that produce mucus. In the nose there are about 150 1 cm2. Mucosal cells equipped with special hairs, or the bottom, which make the continuous oscillatory motion. Their movements we can compare it with how worried shaken by the wind ripe rye. Due to the movement of the cilia formed mucus continuously moves to the side of the nose, to the exit, dragging dust particles, trapped together with air, but detained by cilia and sticking to the wet slime walls pneumatic ways. Up to 5 kg of dust deduce that way from our body during the life of the invisible workers - ciliated cells of the respiratory tract, called due to the nature of their activities atrial cells. The workers of cement plants these cells take over the life of 40 kg of dust.
It is thus clear that the breath through the nose is the only right one, because the air is enough in this case to get warm, and very importantly, it greatly cleaned from dust. Nasal breathing need to be learned and improved. Breathing through the mouth or less full, but it has one important advantage - it is much less resistance to the flow of air, and thus a very fast breaths and more ventilation. Therefore, in the sport at intensive loads, where the volume of respiration in 10-15 times higher than in the rest have to breathe through your mouth. When swimming is almost only used the oral breathing.
After the nose and nasopharynx the air gets into the larynx is the body, the front of which we apparently on his neck in the form of "Adam's Apple". Is larynx from a number of cartilage, especially dense in men, and is characterized by the fact that due to the presence of two "curtains", right and left, its clearance is subject to change. If the curtains tense up and approach, the lumen of the larynx turns into a narrow slit. On the contrary, if the curtains relax and depart from each other, the gap becomes wider. When the curtains are strained, they trembled, shaken by a stream of air flowing, making them not only a part of a pneumatic ways, but also a place of education of the vote, and therefore the curtains are called vocal cords.
After the larynx air gets into the trachea, or windpipe, from there to the right and left bronchi, heading for the light and branching out there on the bronchi a smaller and smaller caliber. Just the bronchial tree has 16 "generations" of the bronchi. Are trachea and bronchi many bonded cartilage rings. The smallest bronchi - bronchioles - bring the air to lung bubbles - the alveoli, where gas exchange.
The exchange of gases in our respiratory includes two stages. On the one hand, there is an exchange between atmosphere and the alveolar air. It is accomplished mainly to the alveoli, by the diffusion of gases in the latest generation of small bronchi. On the other hand, is the exchange of gases between the blood and the alveolar air. This exchange takes place only in the alveoli, which, in fact, represent a point of contact between air and blood. Just bunches of grapes, they surround the bronchiole. Their obletaet creamiest network of blood capillaries. The total area of the alveoli our lungs Reaches almost 90 m2, which greatly facilitates blood contact with air. Only two subtlest layer of cells - the capillary wall and the wall of the alveoli - separating the blood from the air. Through this membrane gases easily pass in both directions. It is here, in the alveoli, the body most closely exposed to chemical substances in the environment. The intestinal wall, through the mucous which absorbed the food is much thicker. The best way to introduce some kind of drug in the blood to direct it into the alveoli. However, the medication should be for this gas, in this connection, this way and cannot be widely applied. It is clear that a solid or liquid, which from the alveoli easily moved in the blood, it is difficult to bring to the alveoli. However, sitting in carbon dioxide or hydrogen sulfide bath, we often think that these gases enter the body through the skin, not realizing how much more important here is their way of penetration through the lungs.
For the regular process of gas exchange, you need to light continuously ventilated, i.e. to fresh air was quickly done, and the fulfilled quickly removed. This acceleration ventilation is due to respiratory movements, rhythmically repeated on average 16 times per minute. Each time the chest cavity expands, and in light absorbed fresh air, and then subsided, squeezing the air, saturated with carbon dioxide and water vapor.
The chest cavity expands when the breath in two ways. Firstly, by reducing external intercostal muscles up the front ends of edges connected to the sternum. The back ends of the ribs attached to the spineand ribs go forward and down. With the reduction of the intercostal muscles of the ribs, revolving around their attachment to the spine, how about the axis, rise, expanding the chest and in the direction from front to back and side to side. Chest circumference increases with breath on 5-8 see that it is easy to check. However, this is only part of the mechanism of breath. Secondly, the chest cavity is increasing and in a downward direction, as aperture, dense muscle wall that separates the chest cavity from the abdominal straining while its average part, usually raised and called "the dome of the diaphragm", is omitted. The increase in the lungs due to lower the aperture you can also check. If you strike the body in that place, which are the organs, containing air, are very different sound than, where is a continuous dense fabric. So the doctors determine the lower bound of the lungs. If you find that line first in the state of breath, and then with a deep breath, you can clearly see that the lower bound of light fell on 7-8 see Because at lowering the aperture she presses on the abdominal viscera, and the last highlighting slightly wall of the abdomen, this element of breathing is called abdominal. Abdominal breathing is expressed in men more than women, which are characterized by the predominance of thoracic breathing. It is not a coincidence. During pregnancy, representing one of the most important items of the female body, the abdominal cavity is largely filled enlarged uterus, which supports the aperture and reduces its mobility. So evolution thoracic breathing became women are predominant.
Light is covered with a smooth, shiny pleura. Another piece of its lines the inside of the chest. In norm between these sheets are not binding, but easy force atmospheric pressure pressed against the wall of the chest cavity. For the same Reason it when inhaling follows expanding the chest cavity. However lung tissue slightly resist it stretching and at the height of inspiration extends not quite as "require" the chest cavity. If at this moment in time between the sheets pleura to measure pressure, it is below atmospheric - an amount equal to the force of elastic resistance of the lungs. However, in the expiratory phase, when the chest cavity is reduced and light zadayutsya, they still remain to some extent, stretched, because at the time the child grows chest grows faster than them. Thus, in adults the pressure between the pleura slightly below atmospheric. There chest cavity has a suction effect, which increases on the breath. This facilitates the flow of blood from veins in the right atrium. Not by chance, some people at the height of breath quickens the pulse - increasing of blood flow causes more intensive work.