Which One of the Following Statements Correctly Describes the Biosynthetic

Multiple Choice

Which one of the following statements correctly describes the biosynthetic pathway for purine nucleotides?

A) Purine deoxynucleotides are made by the same path as ribonucleotides,followed by reduction of the ribose moiety.
B) The first enzyme in the path is aspartate transcarbamoylase (ATCase) .
C) The nitrogen in the purine base that is bonded to ribose in the nucleotide is derived originally from glycine.
D) The pathway occurs only in plants and bacteria,not in animals.
E) The purine rings are first synthesized,then condensed with ribose phosphate.