1. Higher Human Biology Blood Typing

2. ABO Blood Types Four main groups in humans; A B AB O

3. They are categorised by the presence or absence of two types of antigen on the surface of a person’s red blood cells. Remember an antigen is a protein that is found on the surface of a pathogen and which is unique to that particular pathogen. An antigen is recognised by the body as non-self (foreign) Antibodies are present in blood plasma.

4. Blood GroupABABO Antigen on red blood cells A antigensB antigensBoth A and B antigens Neither A nor B antigens Antibodies in blood plasma Anti-B antibodies Anti-A antibodies Neither anti – A nor anti-B antibodies Both anti-A and anti B antibodies

5. From the table we can see that certain blood types are not compatible This can lead to agglutination (clumping) of red blood cells.