Instructions
Overview
 
Problem 1: Tongue Rolling
Tongue Rolling
 
Problem 2: Eye Colour
Eye Colour
 
Problem 3: Diabetes
Diabetes
 
Problem 4: Blood Type
Blood Type
 
Quiz
Quiz
BLOOD TYPE

Red blood cells have many types of molecules sticking out of their cell membranes. Some of these are glycoproteins that determine your blood type.

The genes that code for these glycoproteins exhibit something called "co-dominance" where IA and IB are both equally dominant but O is still recessive.

The genotype for blood type A is written as IAIA or IAi (where "i" is recessive). Blood type B is IBIB or IBi and blood type O is ii.

But put IA and IB together and you get another blood type, AB, the co-dominant type, where neither the A or B is recessive to the other.

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A father has blood type A and a mother has blood type AB. They have 3 children, a son with blood type A, another son with blood type AB, and a daughter with blood type B. The daughter then marries a man with blood type O and they have a daughter with type O.
PEDIGREE







      
Type A male

    
Type B male

    
Type AB male

    
Type O male

    
Type A female

    
Type B female

    
Type AB female

    
Type O female

    
    
homozygous A genotype

    
    
heterozygous A genotype

    
    
homozygous B genotype

    
    
heterozygous B genotype

    
    
codominant AB genotype

    
    
homozygous O genotype

    
    
unknown A and B genotype

    
generations

QUESTIONS
  1. Type the cross for the parents (father x mother) in generation 1.

      


  2. What blood type can the parents in generation 1 NOT produce?

      


  3. What is the best way to write the genotype of the son with type A blood in generation 2?

      


  4. What other blood type can be produced in generation 3?

      


  5. Could the husband of the daughter in generation 2 have blood type B and still produce a type O child?

      


Pedigree Quiz



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