Blood is a biological fluid that constantly circulates in the circulatory system and contains nutrients and gases. Thanks to it, there is a metabolism in the body, tissues and organs receive everything necessary for their life and give away metabolic products. It consists of cells called shaped elements, and plasma. The formed elements of blood make up a little more than 40% of the blood volume, the rest of it falls on the liquid part of the blood - plasma. Blood in the body performs a number of important functions - nutritional, respiratory, protective, heat transfer.
All blood cells are divided into three large groups of cells - red blood cells, white blood cells and platelets. The bulk of the cells are red blood cells, sometimes called red blood cells. It is the red blood cells that give the blood a red color. The main function of red blood cells is to carry out gas exchange, that is, to transport oxygen to the body cells and take carbon dioxide from them . To perform gas exchange, red blood cells contain a special hemoglobin protein. In shape, red blood cells are similar to concave discs on both sides. Thanks to this form, they can easily penetrate into the smallest capillaries. In addition, the concavity on both sides allows you to increase the surface of red blood cells, which is necessary for better oxygen transport. Red blood cells have no nuclei. The life expectancy of these cells is from 90 to 120 days, normally in men, a liter of blood on average contains 5x10 in the 12th degree, and in women - 4.5x10 in the 12th degree of red blood cells.
The next kind of blood cells is white blood cells, that is, white blood cells. These shaped elements play a crucial role in protecting the body from pathogenic bacteria, viruses, and various foreign substances. They cleanse the focus of infection after the destruction of bacteria, produce antibodies that play an important role in the formation of immunity. White blood cells are formed in the bone marrow, spleen, and lymph nodes. These are colorless cells with well-developed nuclei. The content of white blood cells in human blood is 4-10x10 in the ninth degree per liter of blood.
Depending on the presence of granularity in the cytoplasm, leukocytes are divided into granulocytes and agranulocytes. Granulocytes include eosinophils, basophils and neutrophils, while agranulocytes include lymphocytes and monocytes. Each of the forms of white blood cells has its own specialization, is responsible for the implementation of different types of functions.
The shaped elements of the blood called platelets, in fact, are fragments of large cells - megakaryocytes. Platelets are also called blood platelets. Like leukocytes, they are colorless, do not contain nuclei, have an irregular shape. Platelets are extremely variable, quickly destroyed in fresh preparations. Blood plates play a crucial role in the processes of clotting, blood clots and stopping bleeding. The number of platelets in the blood ranges from 200 to 400x10 to 9 degrees per liter of blood.
The shaped elements of blood are formed in the blood-forming organs, which are the bone marrow, lymph nodes, and the spleen. In the body, there is an inextricable connection of shaped elements with the organs in which they are produced and destroyed by the regulation apparatus of this process.
The content of different types of shaped elements is a relatively constant value. Deviations from the norm can be an important symptom of various diseases. The number of different types of blood cells reflects a detailed general blood test with a white blood cell formula. This analysis includes the amount of hemoglobin, color indicator, ESR, blood cells. The analysis table reflects all these indicators in norm, with which you can compare the results.