Лучшие обои для рабочего стола

Blood is a tissue that circulates in the animal's circulatory system, heart and blood vessels. It can send oxygen and nutrients to various organs and carry the metabolic waste of cells away from the cells. Blood tissue is a type of connective tissue composed of plasma and blood cells. Plasma contains various nutrients such as plasma proteins (albumin, globulin, fibrinogen) and lipoproteins, as well as inorganic salts, oxygen, hormones, enzymes, antibodies and cellular metabolites. Blood cells have red blood cells, white blood cells and platelets. The blood of the mammal has a blood coagulation mechanism. When the blood vessel ruptures, the platelets will accumulate and block the blood vessel to break. At this time, the originally water-soluble fibrin in the plasma solidifies into a blood clot, and the remaining transparent liquid is called serum.