Carbon Dioxide

Carbon dioxide is a colorless and odorless gas that naturally generates a small amount of gas in the atmosphere of the earth. The earth's ocean, soil, plants and animals emit carbon dioxide. The equation of carbon dioxide is CO2. Carbon dioxide molecules contain two oxygen atoms, each of which shares two electrons with a carbon atom to form two carbon-oxygen double bonds. The atomic array is this (OHT). This is called "linear molecule". Carbon dioxide is usually seen as a gas, it is never liquid. Because it is cooler and less melting it sublimes to a solid called "dry ice" which is used as a substitute for ordinary ice.

Carbon dioxide is transported into the blood by three different mechanisms: dissolved carbon dioxide, bicarbonate, and carbamoyl hemoglobin. A small amount of carbon dioxide is still present. The maximum amount of carbon dioxide transport is bicarbonate formed in erythrocytes. For this conversion carbon dioxide is mixed with water by an enzyme called carbonic anhydrase. This combination forms carbonic acid, which spontaneously dissociates into bicarbonate and hydrogen ions. When bicarbonate accumulates in red blood cells, it exchanges chloride ions by mechanism called chloride ion migration and migrates through the membrane into the plasma. In lung capillaries, bicarbonate re-enters red blood cells in exchange for chloride ions, and the reaction with carbonic anhydrase reverses to reconstitute carbon dioxide and water. Carbon dioxide then diffuses from the red blood cells through the respiratory membrane into the air. This is an example of Haldane effect

Carbon dioxide is carried through three main mechanisms. The first mechanism of carbon dioxide transport is plasma. Because some carbon dioxide molecules are soluble in blood. The second mechanism is transported in the form of bicarbonate (HCO 3 -), which is also dissolved in the plasma. The third mechanism of carbon dioxide transport resembles red blood cell transport of oxygen (Figure 4). Carbon dioxide is thought to be difficult to dissolve in blood, but it spreads from tissue to a small part of blood. Approximately 7 to 10% of carbon dioxide is dissolved in plasma. When blood reaches the lung capillary, dissolved carbon dioxide diffuses through the respiratory membrane into the alveoli and exhales during ventilation of the lungs.

Most - approximately 70% of the carbon dioxide molecules diffuse into the bloodstream and are carried to the lungs as bicarbonate. Most of the bicarbonate is produced in red blood cells after carbon dioxide has diffused into the capillary and then into the red blood cells. Carbonic anhydrase (CA) forms carbonic acid (H 2 CO 3) in carbon dioxide and water, which decomposes into two ions, bicarbonate (HCO 3 -) and hydrogen (H +). This reaction is explained by the following formula. Since bicarbonate tends to accumulate in red blood cells, the bicarbonate concentration of erythrocytes will be higher than the bicarbonate concentration of the surrounding plasma. As a result, some bicarbonate exits the erythrocyte and moves its concentration gradient into the plasma in exchange for chloride (Cl -) ions.