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Human Blood Groups- Multiple Alleles AND CoDominance. OK… Humans and many other primates. Recall: There are three different alleles for human blood type (multiple alleles):.
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Human Blood Groups-Multiple Alleles AND CoDominance OK… Humans and many other primates
Recall: There are three different alleles for human blood type (multiple alleles): • “A” indicates the presence of 1 type of antigen (protein that can “activate” your immune system) and “B” represents a different antigen on the surface of a red blood cell • “O” has no antigen on the surface of the RBC
Antibodies • A “foreign” antigen will trigger your immune system to create antibodies. • Since antibodies are proteins, they have a specific shape & will attach onto the antigen for which they were made. • There are bacteria in the atmosphere that have a very similar shape to our “A” and “B” antigens & we are exposed to them as soon as we are born.
Therefore, each person can have antibodies against an antigen they didn’t inherit. • These antibodies are floating around in our blood with our RBC’s.
Type A blood (has A antigens on cell surface) has Anti-B antibodies • Antibodies are named for what they attack • Anti-B antibodies attack and will clump up (agglutinate) in the presence of B-antigen • Type B blood (has B antigens on cell surface) has A-antibodies
Type AB blood doesn’t have any antibodies • Type O blood has Anti-A and Anti-B antibodies
Rh Factor • The Rh factor genetic information is also inherited from our parents, but it is inherited independently of the ABO blood type alleles (a separate gene).
There are 2 different alleles for the Rh factor known as Rh+ and Rh-. • Normal dominant/recessive inheritance • Positive (+) allele is dominant to negative (-) allele • Rh +: you have the protein Rh-: you don’t