Download O Negative Blood Type History Images. A blood type (also known as a blood group) is a classification of blood, based on the presence and absence of antibodies and inherited antigenic substances on the surface of red blood cells (rbcs). The rh negative blood type is said to be of unknown origin.

The body will attack any foreign antigen, e.g., a person with blood group b will be having b antigen on the red blood cells and therefore a.

Blood group matching is important so that the transfused blood is not attacked by the immune system of the recipient. Blood type 'ab' is the least common. Air ambulances and emergency response vehicles carry o negative supplies for emergencies. Generally speaking, type o can donate to everyone sometimes problems can occur when a mother's blood does not match her baby's.