the closed cardiovascular system, providing an exchange of gases
in lungs and tissues of a body. The system of blood circulation consists of heart and the blood vessels.Besides providing fabrics and bodies oxygen and removals from them of carbonic acid, blood circulation delivers nutrients, water to cages, salts, vitamins, hormones and deletes the final products of a metabolism, and also maintains constancy of body temperature, provides humoral regulation and interrelation of bodies and systems of bodies in an organism.
Blood circulation begins in fabrics where the metabolism through walls of capillaries is made. The blood which has given oxygen to bodies and fabrics, arrives in the right half of heart and the blood circulation circle where blood is sated with oxygen goes them in small (pulmonary), comes back to heart, arriving in its left half, and again is carried on all organism (a big circle of blood circulation).