called cytosine (C), occurs in both types of nucleic acid. A second pyrimidine, called thymine (T), only occurs in DNA, while the third type, uracil (U), only occurs in RNA. Nitrogenous bases are ...

Levene proposed that nucleic acids were composed of a series of nucleotides, and that each nucleotide was in turn composed of just one of four nitrogen-containing bases, a sugar molecule ...

In the late nineteenth century, a German biochemist found the nucleic acids, long-chain polymers of nucleotides, were made up of sugar, phosphoric acid, and several nitrogen-containing bases.

characteristic of the cyclic nitrogenous bases present in the nucleic acids. In contrast, the homologous mature tissues exhibit a different absorption similar to that of the proteins.

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 ...

The structure of a nucleotide, consisting of a phosphate group (left), a pentose sugar molecule (middle), and a nitrogenous base (right ... nucleobases and nucleosides from the breakdown of nucleic ...