Which liver enzyme is missing in infants with phenylketonuria?
A)phenylalanine hydroxylase
B)phenylalanine hydrochlorase
C)phenylalanine ketonase
D)ketonase

Question

Quizplus · Accepted Answer

Infants with phenylketonuria are missing the enzyme phenylalanine hydroxylase, which is responsible for converting phenylalanine into tyrosine in the liver. The absence of this enzyme results in the buildup of phenylalanine and its byproducts in the blood and brain, leading to neurological and developmental problems. The other enzyme choices listed (B, C, and D) are not involved in the metabolism of phenylalanine.

Which Liver Enzyme Is Missing in Infants with Phenylketonuria