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
[{'content': 'PRPP (Phospho Ribosyl Pyro Phosphate) is used in : \nSelect and explain. \nA. Purine synthesis & Pyrimidine synthesis, B. Histidine synthesis, C. Niacin synthesis, D. All', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Phosphoribosyl Pyrophosphate(PRPP) is used in the synthesis of : 1. Purine 2. Pyrimidine 3. Histidine 4. Niacin synthesis from Tryptophan. NOTE: Phosphoribosyl pyrophosphate (PRPP) paicipates in pyrimidine biosynthesis only subsequent to assembly of the pyrimidine ring. PRPP serves as a scaffold for assembly of the purine ring in purine biosynthesis. The first intermediate formed in the de novo pathway for purine biosynthesisis 5-phosphoribosyl 1-pyrophosphate (PRPP).', 'role': 'assistant'}]