HEREDITY
THE PEDIGREE
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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one parent with type AB blood, and the other parent with type A blood
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one parent with type AB blood and the other parent with type O blood
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one parent with heterozygous type A blood, and the other parent with type O blood
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one parent with homozygous type A blood, and the other parent with homozygous type B blood
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Detailed explanation-1: -The condition where no antigens are present on the blood cells (type O blood) is a recessive trait. Which set of parents can most likely produce a child with type O blood? One of the parents of a child has phenylketonuria (PKU), which is caused by recessive alleles. The other parent does not have the PKU alleles.
Detailed explanation-2: -Alleles IA and IB are considered codominant as both these alleles dominate over recessive allele.
Detailed explanation-3: -AB blood type is codominant because the red blood cells have the products of both the A and the B alleles of the ABO gene.
Detailed explanation-4: -Someone with blood type O has neither the A nor the B allele. The genotype must be OO.
Detailed explanation-5: -If alleles for a trait are codominant, they will both be equally and fully expressed. This is a bit different than incomplete dominance, in which the traits are blended. A common example given to describe codominant traits is the ABO blood typing system. There are three possible alleles for ABO blood type: A, B, and O.