Wait, what is blood type? Although all blood is made of the same basic elements, not all blood is alike. Blood types are determined by the presence or absence of certain antigens – substances that tell the immune system to attack! These antigens are called “A”, “B”, and Rh (+ if you have it, - if you don’t)

Blood Typing Key Point #1: Blood type has three alleles: IA, IB, and i. IA & IB are dominant i is recessive Before KP#3, ask students if they know their blood type. 2

Blood Type Genotype Key IA IA = Type A (homozygous) IA i = Type A (heterozygous) IB IB = Type B (homozygous) IB i = Type B (heterozygous) IA IB = Type AB i i = Type O

Universal Donor Blood type O can give(donate) blood to ANYONE because they have no antigens on their blood

Universal Receiver AB blood is the universal receiver because it has both A and B antigens. This means someone with AB blood can receive type A blood, type B blood, type AB blood and type O blood!

Blood Typing IB IA IA IAIB IAIB IA IB IAIB GENOTYPES: PHENOTYPES: Show the potential offspring between a mother who is homozygous for Type A blood and a father who is homozygous for Type B blood. IA IA GENOTYPES: IB IAi: 0% IBi: 0% IAIB: 100% ii: 0% IAIB IAIB IA IB IAIB PHENOTYPES: Type A: 0% Type B: 0% Type AB: 100% Type O: 0%

A little practice Only some combinations of parents will make certain blood types. Example: An Iai mother and an ii father can never make a baby that is IAIB Because of this, blood type can sometimes be used to determine paternity (who are the parents of a baby)

Who are the parents?!?!

Scenario 1 Katie is heterozygous for Type A blood (IAi). Her baby is type O (ii). She is not sure if Richard, her husband, or Adam, her husband’s best friend, is the father… Richard has type AB blood (IAIB ) Adam has type B blood (IBi)

Katie’s baby is type O (OO). Who is the father?!?!?! Adam Richard IB i IA IB IAIB IAi IA IA AB IA IA Katie IBi ii IAi Ibi i i

Scenario 2 Samantha has type AB blood and so does her baby. She is not sure whether Nick or Ron is the father of her baby…. Nick has type O blood Ron has type B blood (homozygous) Which one is the father? Use Punnett Squares to prove it. 11

Samantha has type AB blood and so does her baby. Nick Nick could not have a child with Samantha who has AB blood!!!!! So, Ron is the dad! i i IAi IAi IA Sam IBi IBi IB

Scenario 3 Jackson is heterozygous for Type B blood, and his mother has Type AB blood. His father has Type AB blood, also. What does this mean?! (Prove your answer with a Punnett Square!)

JACKSON IS ADOPTED (OH SNAP!!!) IA IB IA IA IA IB IA Jackson is IBi I B IA IB IB IB

Let’s Party!!!!!!! What happens when blood type reveals two people have been switched at birth?