Nucleotide: A molecule made up of a sugar, a phosphate group, and a nitrogenous base (which can be either a purine or pyrimidine), forming the basic structural unit of nucleic acids like DNA and RNA.
Adenine:A type of purine base that pairs with thymine in DNA and uracil in RNA, playing a key role in coding genetic information.
Guanine:Another type of purine base that pairs with cytosine in both DNA and RNA, crucial for maintaining the structure and function of genetic material