ribonucleic

Ribonucleic refers to ribonucleic acid, one of the two main families of nucleic acids. Nucleic acids are polymers of nucleotides; in ribonucleic acid the sugar component is ribose, the bases are adenine, cytosine, guanine and uracil, and the backbone is formed by phosphate groups linked to sugar moieties. RNA is typically single-stranded, though it can fold back on itself to form complex secondary and tertiary structures through base pairing.

In cells, RNA plays essential roles in decoding and expressing genetic information. Messenger RNA (mRNA) carries genetic information from DNA to ribosomes for protein synthesis; transfer RNA (tRNA) and ribosomal RNA (rRNA) participate directly in translation; many other RNA types regulate gene expression and genome defense, including microRNAs and small interfering RNAs. Some RNA molecules act as enzymes (ribozymes) that catalyze biochemical reactions. RNA viruses use RNA as their genetic material; RNA is generally less chemically stable than DNA due to the 2' hydroxyl group, making it more prone to hydrolysis and mutation, contributing to higher evolutionary rates.

Ribonucleic acid is named to distinguish from deoxyribonucleic acid (DNA), which contains deoxyribose and thymine and is typically double-stranded. The term ribonucleic is widely used in formal contexts as part of the full name.