Blood Cells
A basic understanding of Blood Types
Red blood cells have antigens, which are proteins, on their cell membrane. There are four different types of antigens that are attached to blood cells: A, B, AB, and O. Each different type of blood contains a different protein, and the blood is codominant because each antigen that is present is expressed in the cell. Blood cells contain antibodies which allows blood with the same antigens to coexist peacefully together while blood cells with different antigens agglutinate together. The agglutination, clumping together of cells, can be fatal to the organism because the blood cells clog up the arteries and veins which blocks the flow of oxygen throughout the body. For example, blood type A can only exist with blood type A because they contain the same antigens. If you put blood type B in an organism that has blood type A, the blood cells will agglutinate and the organism will die unless it is noticed immediately. There are some chemicals that can stop the agglutination of blood cells, but if the blood is mixed in mass quantities there is little chance for survival. On the otherhand, if a person inherits type AB blood, they have antigens for all blood types and can accept any type of blood. Type O blood is the absence of proteins on the blood cell and can be given to an organism of any blood type. Type O is commonly referred to as the universal donor because anybody can accept it. It is used in accidents where a lot of blood is lost until the persons blood type can be determined. In genetics blood types are commonly seen in different forms than they are written in this paper. The blood types are seen as follows: Type A blood- IAIA or IAi, type B blood- IBIB or IBi, type AB blood- IAIB, and type O blood- ii. The capital letter refers to the presence of an antigen while the lower case refers to the absence of antigens. The letters on the superscript of the letter refer to the blood type.