Women with PKU Must Avoid the Essential Amino Acid Phenylalanine

Multiple Choice

Women with PKU must avoid the essential amino acid phenylalanine and consume a diet low in protein because _____.

A) they lack enough stomach acid (HCl) to break down dietary proteins, including phenylalanine
B) they are allergic to phenylalanine and other protein-rich foods
C) they lack the enzyme necessary to convert phenylalanine to tyrosine
D) phenylalanine and protein-rich foods cause acid to build up in blood
E) they are unable to incorporate phenylalanine into proteins, so it builds up in blood, potentially blocking blood vessels