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)
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.
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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.
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The children will all have type A blood.
To determine the possible blood types of the children, we need to understand how codominance works in relation to the A and B alleles.
In codominance, both alleles are expressed equally and simultaneously. In the case of blood typing, both the A and B alleles are codominant. This means that if an individual has both A and B alleles, they will have the AB blood type.
Given that the man is homozygous for type A blood (genotype AA) and the woman is homozygous for type B blood (genotype BB), we can determine the potential genotypes of their children.
Each parent can only pass on one allele to each child. The man can only pass on an A allele, and the woman can only pass on a B allele. Therefore, each child will receive one A allele from the man and one B allele from the woman. The resulting genotype for all the children would be AB.
Therefore, the correct answer is: The children will all have type AB blood.