Packed red blood cells Rh type, specifically the phenotype, and the "screen" refers to testing for atypical antibodies that might cause transfusion problems. The typing and screening are also performed on donor blood. The blood groups represent antigens on the surface of the red blood cells which might react with antibodies in the recipient. The ABO blood group system has four basic phenotypes: O, A, B, and AB. In the former Soviet Union these were called I, II, III, and IV, respectively. There are two important antigens in the system: A and B. Red cells without A or B are called type O, and
Blood ritual The Aztecs believed the gods would provide plentiful crops and healthy long lives as long as blood was ritually given (Pendragon 2). If blood was not sacrificed to the gods, the humans believed they would be punished and endure excessive pain “more violent than any man could ever do” (Pendragon 3). Some Indians practice a political ritual voluntarily where the people donate blood as a way to remember politicians who have died (Copeman 126). The blood donation is literally a donation to people who need transfusions (Copeman 132). The participants donate at donation camps during the birthday or the anniversary