Hemolytic Disease of the Newborn Can Occur If the Mother

question 21

Multiple Choice

Hemolytic disease of the newborn can occur if the mother is:

• A)Rh-positive and the fetus is Rh-negative.
• B)Rh-negative and the fetus is Rh-positive.
• C)type A blood and the fetus has type O.
• D)type AB blood and the fetus has type B.

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Definitions:

Recessive Allele

An allele that produces its characteristic phenotype only when its paired allele is identical.

Dominant Allele

A dominant allele is one version of a gene that masks the presence of a recessive allele in the pair, meaning the trait it represents is expressed even when only one copy is present.

Codominance

A genetic scenario where two alleles of a gene are expressed equally in the phenotype of the organism, neither being recessive to the other.

Polygenic Inheritance

Refers to the contribution of a variety of genes—sometimes very many—to a particular trait.