試題詳解

22. The human genetic disease phenylketonuria (PKU) can result from_______ .
(A) lack of phenylalanine decarboxylase
(B) deficiency in aromatic amino acid transaminase
(C) a deficiency of protein in the diet
(D) overproduction of ketone bodies
(E) lack of an enzyme required for converting phenylalanine to tyrosine