Purines are nitrogen-containing compounds that are found in both DNA and RNA. They are essential building blocks of these nucleic acids, which are responsible for carrying genetic information and controlling cellular functions. Some common synonyms for the word purine include nitrogenous bases, nucleobases, adenines, guanines, cytosines, and thymines. Nitrogenous bases refer to any type of organic compound that contains nitrogen and acts as a base. Nucleobases are the individual units that make up DNA and RNA. Adenine and guanine are the two purines found in both DNA and RNA, while cytosine and thymine are two pyrimidines found only in DNA. These synonyms for purines all refer to different aspects of the complex nucleic acid structures that are crucial to life as we know it.