What are the functions of the circulatory system?
Blood and other biological fluids, such as lymph and tissue fluid, form the internal environment of the body. Blood is a special kind of connective tissue, because it is phylogenetically and ontogenetically formed from the connective tissue of the germinal unit - the mesenchyme. The circulatory system is a network of vessels and cavities of the heart, through which there is a constant and uninterrupted circulation of blood. What are the functions of the circulatory system? Answering this question, you can write a whole scientific treatise, because the functions of the circulatory system are diverse. This is the transportation of vital substances and biologically active compounds that provide nutrition and further development of all cells and tissues of the human body, this is the vital function of gas exchange, and this is the maintenance of osmotic pressure by protein fractions circulating in the bloodstream. The creation of an immune response adequate to the influence of external and internal factors, which could protect the body from infectious agents and other foreign elements alien to each individual, belongs to the function of the circulatory system of man.
The circulatory system would not have been able to take place if there had not been a constant, continuous lifelong movement of blood, called blood circulation. The heart with an infinite number of blood vessels( large arteries, venous vessels, arterioles, capillaries and venules), as well as the lymphatic system constitute a single vascular system of the human body. The function of the circulatory system includes the removal of oxidation products and other reactions that occur during the metabolism, which become very dangerous and toxic for cellular elements, if they are not eliminated from the body in time. Structural elements of blood create humoral regulation and provide full control of the activity of all internal organs and each of the systems.
Blood, as a material substance of the circulatory system, consists of two parts: liquid, or plasma, as well as dry cocking of the formed elements( platelets, erythrocytes and leukocytes).The ratio of these fractions on average is 1: 1.5, and in percentage plasma belongs to 40%, and shaped elements 60% of the total blood. Plasma( liquid part) is a very complex and unique biological environment, 90% of which is water. The remaining 10% of the total plasma falls on proteins, amino acids, mineral complexes, glucose, buffer systems, hormones, dissolved gases, vitamins, enzymes, and the like.
Functions of the circulatory system to ensure humoral immunity are associated with blood plasma. With regard to the uniform elements, it should be said that they have three completely different functions: in erythrocytes - respiratory, in leukocytes - protective, in platelets - coagulating.
In erythrocytes, an important iron-containing pigment is contained, which is called hemoglobin. Due to this, oxygen is transported from the outside air to the cells, and from the cells carbon dioxide is released into the external environment. There are several forms of leukocytes, and each of them has its own vital task. They create cellular immunity, with their deficiency develop dangerous pathological conditions, a vivid example of which is HIV infection. Clotting ability and aggregation property is inherent only in platelets, their deficiency causes abnormal bleeding, both external and internal, and excess can cause the formation of thrombi that clog the lumen of blood vessels and block the normal flow of blood.
Whatever the functions of the circulatory system, its role in human life is indisputable.