# Alleles H and I are codominant, j is recessive to both. How many phenotypes are possible in a flock of ducks that contains all possible combinations of the 3 alleles?I would like to know what the...

Alleles *H* and *I* are codominant, *j* is recessive to both. How many phenotypes are possible in a flock of ducks that contains all possible combinations of the 3 alleles?

I would like to know what the possible phenotypes are and how you recieved the answer.

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This question is a great deal like the ABO blood type in humans. In fact, type A and B are codominant and O is recessive. In humans, there are the following phenotypes--type AB, Type A, Type B, and Type O. If we compare this to the question about a flock of ducks, the four phenotypes are--HI-since H and I are codominant, these two genes will both be expressed, there will be H--which can occur if a duck has two H genes, or if a duck has an H and a J gene(recessive). There will be ducks with I--this can occur if the duck has two I genes, or an I and a J(recessive)gene combination. Finally, there will be ducks with J--the recessive trait--these ducks will have two J genes. Therefore, just like in the human blood type example, the ducks will have four distinct phenotypes.

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