Blood type namely group A, group B, and group C. He defined that group A blood agglutinates with group B, but never with its own type. Similarly, group B blood agglutinates with group A. Group C blood is different in that it agglutinates with both A and B. This was the discovery of blood groups for which Landsteiner was awarded the Nobel Prize in Physiology or Medicine in 1930. (C was later renamed to O after the German "Ohne", meaning without, or zero, or null.) The group AB was discovered a year later by Landsteiner's students Adriano Sturli, and Alfred von Decastello.
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