Kossel isolated cytosine from calf thymus tissues and found that it was a component of nucleic acids. This discovery, along with the identification of other nitrogenous bases, laid the foundation for ...

and a nitrogenous base. Adjacent ribose nucleotide bases are chemically attached to one another in a chain via chemical bonds called phosphodiester bonds. Unlike DNA, RNA is usually single-stranded.

With a composition quite similar to DNA, RNA is able to perform a variety of biological functions conditioned ... RNA is formed by linking molecules of ribose (a monosaccharide) with phosphate groups ...