Answer to Question 1
ANS: B
PKU is an inborn error of metabolism caused by a deficiency or absence of the enzyme needed to metabolize the essential amino acid phenylalanine. Phenylalanine hydroxylase is missing in PKU. Individuals with this disorder can metabolize glucose. Phenylketones are metabolites of phenylalanine, excreted in the urine. Thyroxine is one of the principal hormones secreted by the thyroid gland.
Answer to Question 2
ANS: D
Newborns born to mothers who smoke had growth failure in weight, length, and chest circumference when compared with newborns of mothers who did not smoke. A dose-effect relation exists. Newborns have significant growth failure, which is related to the number of cigarettes smoked.