The blood vessels carry blood throughout the body and can be divided into three main blood vessels types: the arteries – carrying the blood from the heart, the capillaries – allowing the exchange of water and chemicals between the blood and the tissues, and the veins – transporting blood to the heart from the capillaries. [...]
Even before person is born its blood type is established because it represents combination of parent’s genes. Blood type or blood group is determinate by antigens A, B or O presence in blood and Rh +/- factor so there is following types: 0 +/-, A +/-, B +/- and AB +/- . Frequency of certain [...]