Answer to Question #253972 in General Chemistry for Jane

Question

Why can an individual with Type B blood receive only blood types B and O, but he or she can

donate individuals with either type B or AB blood?

Answer 1

Human blood type – A, B, AB, or O - is determined by three or four monosaccharides attached to membrane protein on the surface of red blood cells. There are three different carbohydrate sequences, one for each of the A, B, and O blood types. Blood type AB contains the sequences for both blood type A and blood type B.

Since the blood of an individual may contain antibodies to another blood type, blood type must be known before receiving a transfusion.

An individual with type B blood can receive only blood types B and O, because he or she will produce antibodies and an immune response to A or AB blood. He or she can donate to individuals with either type B or AB blood as the type B polysaccharides are common to both and no immune response will be generated.