This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Nucleotides, Subject name: Biochemistry
Nitrogen atoms in purines are derived from all except- 
Select and explain. 
A. Aspaate, B. Glutamine, C. Glutamate, D. Glycine
C: Glutamate
Answer: C: Glutamate 
Explanation: Nitrogen atoms in purines are derived from amino acids - Aspaate Glutamine Glycine Nitrogen atoms in purines Carbon atoms in purines N1 from Aspaate C2 from N10Formyl Tetrahydrofolate N3 & N9 from Glutamine C4 and C5 from Glycine N7 from Glycine C6 from CO2 C8 from N5,N10Methenyl THF