試題詳解

30. Which of the following descriptions is false?
(A) The conversion of glutamate to an a-keto acid and NH4 is accompanied by ATP hydrolysis.
(B) Most amino acids are metabolized in the liver; however, the three amino acids with branched side chains (leucine, isoleucine, and valine) are oxidized as fuels primarily in muscle, adipose, kidney, and brain.
(C) In liver mitochondria, glutaminase catalyzes the reaction to release the amino group from glutamine; the products are glutamate and ammonia.
(D) Genetic defects in the urea cycle can not be treated by a protein-free diet.
(E) Alanine can play the role to transport ammonia from skeletal muscles to the liver. In muscles, glutamate can transfer its a-amino group to pyruvate to form alanine by alanine aminotransferase.