Codominance is a form of inheritance in which two different alleles for a gene are both expressed, and neither allele is dominant over the other. The alleles for type A blood and type B blood are codominant. If a man who is homozygous for type A blood and a woman who is homozygous for type B blood have children, what would you expect to find in the children? (2 points)

Question

Half will have type A and half will have type B blood.

The children will all have type B blood.

The children will all have type AB blood.

The children will all have type A blood.

Answer 1

Since Jiskha doesn't have a biology expert at this time, please try posting your question at this site.

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Answer 2

Codominance means both are expressed in the presence of each other. If there is one allele of each, then both A and B will be expressed (giving AB type).
If either an A allele is paired with a different one, such as O, then the dominance is expressed and the resulting blood type is A. Similar phenomenon with B.

Since one parent is homozygous with A type (i.e. AA) and the other is homozygous with B type (i.e. BB), then the children will always have an A allele and a B allele,giving AB blood type in all cases.

The above reading recommendations from Writeacher are excellent. In particular, read up on sickle cell anemia alleles. It is even more interesting.