What Is the Five-Carbon Sugar Found in RNA?

The five-carbon sugar found in RNA is ribose. Ribose is an important carbohydrate for generating energy in the cells of living organisms.

Ribonucleic acid, or RNA, is a type of complex organic substance found primarily in the material within a living cell. RNA contains the codes that allow it to replicate itself. Its key role is synthesizing proteins. Deoxyribonucleic acid, or DNA, is a molecule found primarily in the nucleus of cells that contains the codes to make RNA.

RNA comprises a long chain of nucleotides, each of which consists of a sugar, phosphate and nitrogen-containing base. The sugar is called ribose, which is a five-carbon, or pentose, sugar. Ribose is a monosaccharide carbohydrate that plays a major role in producing adenosine triphosphate, or ATP, which is an important source of energy for cells. DNA also features a sugar called deoxyribose. Ribose and deoxyribose differ by one oxygen atom.

Ribose has a chemical composition that repels the electrostatic negative charge of the phosphate, according to Stanford University. This repulsion means that the RNA chain cannot coil in a tight helix in the same way as DNA. This gives RNA greater flexibility and a less structured form, but DNA is a more stable substance.