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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
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About purine and pyrimidine nucleotides, all are true except-
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The correct answer is  Ans. is 'c' i.e., Adenosine is a nucleotide o Two types of bases are found in nucleotides : (i) purines and (ii) pyrimidines.i) Purines : Two major purine bases found both in DNAs as well as RNAs are (i) adenine (A) and (ii) guanine (G).ii) Pyrimidines: Three major pyrimidine bases are (i) cytosine (C), (ii) Uracil (U) and (iii) Thymine (T). Cytosine and uracil are found in RNAs and cytosine and thymine are found in DNAs. Uracil is notfound in DNAs Q and thymine is not found in RNAs.Different major bases with their corresponding nucleosides and nucleotidesBaseRibonucleosideRibonucleotideAdenine (A)Guanine (G)Uracil (U)Cytosine (C)AdenosineGuanosineUridineCytidineAdenosine monophosphate (AMP)Guanosine monophosphate (GMP)Uridine monophosphate (UMP)Cytidine (Monophosphate) (CMP)BaseDeoxy ribonucleosideDeoxyribonucleotideAdenineGuanineCytosineThymineDeoxyadenosineDeoxyguanosineDeoxycytidineDeoxythymidineDeoxyadenosine monophosphate (dAMP)Deoxyguanosine monphosphate (dGMP)Deoxycytidine monophosphate (dCMP)Deoxythymidine monophosphate (dCMP)o Thus adenosine is a nucleoside (not nucleotide)Nucleoside= Nitrogenous base (purine or pyrimidine) + Pentose sugar (ribose or deoxyribose)Nucleotide= Nucleoside + phosphate group (phosphoric acid)or= Nitrogenous base + Pentose sugar + Phosphate group