NURSING ANM AND GNM

Detailed explanation-1: -The purines (adenine and guanine) have a two-ringed structure consisting of a nine-membered molecule with four nitrogen atoms, as you can see in the two figures below. The pyrimidines (cytosine, uracil, and thymine) only have one single ring, which has just six members and two nitrogen atoms.

Detailed explanation-2: -The purines have a double ring structure with a six-membered ring fused to a five-membered ring. Pyrimidines are smaller in size; they have a single six-membered ring structure.

Detailed explanation-3: -purine, any of a class of organic compounds of the heterocyclic series characterized by a two-ringed structure composed of carbon and nitrogen atoms. The simplest of the purine family is purine itself, a compound with a molecular formula C5H4N4.

Detailed explanation-4: -Purine is a heterocyclic aromatic organic compound that consists of two rings (pyrimidine and imidazole) fused together.