Что такое газообмен?Almost no living creature can do without it. Gas exchange in the lungs and tissues, as well as blood, helps saturate cells with nutrients. Thanks to him, we get energy and vitality.
What is gas exchange?
For the existence of living organisms is necessaryair. It is a mixture of many gases, most of which are oxygen and nitrogen. Both of these gases are essential components for the normal functioning of organisms.
In the course of evolution, different species developed theirdevices for obtaining them, some have developed lungs, others have gills, and still others use only the integuments. With the help of these organs is gas exchange.
What is gas exchange?It is a process of interaction between the environment and living cells, during which oxygen and carbon dioxide are exchanged. During breathing, oxygen enters the body along with air. Saturating all cells and tissues, it participates in the oxidative reaction, turning into carbon dioxide, which is excreted from the body along with other products of metabolism.
Lung gas exchange
Каждый день мы вдыхаем больше 12 килограмм of air. This helps us lungs. They are the most voluminous organ capable of holding up to 3 liters of air in one full deep breath. Gas exchange in the lungs occurs with the help of alveoli - numerous bubbles that are intertwined with blood vessels.
Air enters them through the upper respiratorypaths, passing trachea and bronchi. The capillaries connected to the alveoli take the air and carry it through the circulatory system. At the same time, they give carbon dioxide to the alveoli, which leaves the body along with the exhalation.
Процесс обмена между альвеолами и сосудами called bilateral diffusion. It takes only a few seconds and is due to the difference in pressure. In atmospheric air saturated with oxygen, it is more, so it rushes to the capillaries. Carbon dioxide has less pressure, which is why it is pushed into the alveoli.
Circulation
Without circulatory system, gas exchange in the lungs andTissues would be impossible. Our body is permeated with many blood vessels of various lengths and diameters. They are represented by arteries, veins, capillaries, venules, etc. In the vessels, the blood circulates continuously, promoting the exchange of gases and substances.
Gas exchange in the blood is carried out with the help of twoCircles of blood circulation. When breathing, the air begins to move in a large circle. In the blood, it is transferred by attaching to a special protein, hemoglobin, which is contained in red blood cells.
From the alveoli air enters the capillaries, and then inarteries heading straight for the heart. In our body, it plays the role of a powerful pump, pumping oxygenated blood to tissues and cells. They, in turn, give blood filled with carbon dioxide, directing it through the venules and veins back to the heart.
Passing through the right atrium, venous bloodcompletes a large circle. In the right ventricle begins a small circle of blood circulation. According to him, the blood is distilled into the pulmonary trunk. It moves through the arteries, arterioles and capillaries, where it exchanges air with the alveoli to start the cycle again.
Exchange in tissues
So we know what lung gas exchange is.blood. Both systems carry gases and exchange them. But the key role belongs to the tissues. They are the main processes that change the chemical composition of air.
Arterial blood fills cells with oxygenwhich runs into them a whole range of redox reactions. In biology, they are called the Krebs cycle. For their implementation are necessary enzymes that also come with blood.
During the Krebs cycle, citric, aceticand other acids, products for the oxidation of fats, amino acids and glucose. This is one of the most important stages that accompanies gas exchange in the tissues. During its flow, the energy necessary for the functioning of all organs and body systems is released.
For the implementation of the reaction is actively used oxygen. It gradually oxidizes, turning into carbon dioxide - CO2which is released from cells and tissues into the blood, then into the lungs and the atmosphere.
Gas exchange in animals
Строение организма и систем органов у многих animals varies greatly. The most similar to humans are mammals. Small animals, such as planarians, do not have complex systems for the exchange of substances. For breathing, they use external covers.
Амфибии для дыхания используют кожные покровы, а also mouth and lungs. In most animals that live in water, gas exchange is carried out using the gills. They are thin plates connected to the capillaries and transporting oxygen from water into them.
Arthropods, such as centipedes, woodlice,spiders, insects, do not possess lungs. Over the entire surface of the body, they have tracheas that direct the air directly to the cells. Such a system allows them to move quickly without experiencing shortness of breath and fatigue, because the process of energy formation occurs faster.
Gas exchange in plants
В отличие от животных, у растений газообмен в The tissues include the consumption of both oxygen and carbon dioxide. Oxygen they consume in the process of breathing. Plants do not have special organs for this, so air enters them through all parts of the body.
Как правило, листья имеют наибольшую площадь, и most of the air falls on them. Oxygen enters them through small openings between the cells, called stomata, is processed and excreted in the form of carbon dioxide, as in animals.
A distinctive feature of plants isability to photosynthesis. So, they can convert inorganic components into organic using light and enzymes. During photosynthesis, carbon dioxide is absorbed and oxygen is produced, therefore the plants are real "factories" for enriching the air.
Features
Gas exchange is one of the most important functions.any living organism. It is carried out with the help of breathing and blood circulation, contributing to the release of energy and metabolism. Features of gas exchange are that it does not always proceed in the same way.
First of all, it is impossible without breathing, itsstop for 4 minutes can lead to disruption of the brain cells. As a result, the body dies. There are many diseases in which there is a violation of gas exchange. The tissues do not receive enough oxygen, which slows down their development and function.
Uneven gas exchange is observed andhealthy people. It increases significantly with increased muscle work. In just six minutes, it reaches its ultimate power and adheres to it. However, as the load increases, the amount of oxygen may begin to increase, which will also have an unpleasant effect on the body's well-being.
