RNA

Ribonucleic acid (RNA), is one of the three major macromolecules (along with DNA and proteins). Like DNA, RNA is made up of a long chain of components called nucleotides. Each nucleotide consists of a nucleobase, a ribose sugar, and a phosphate group. Unlike DNA, most RNA molecules are single-stranded. The sequence of nucleotides allows RNA to encode genetic information.

RNA has many functions in the body and are therefore usually distinguishes many different subtypes, eg:

• mRNA carries the genetic information that directs the synthesis of proteins,
• rRNA links amino acids together to form proteins,
• tRNA delivers amino acids to the ribosome.

Some RNA molecules play an active role in cells by catalyzing biological reactions, controlling gene expression, or sensing and communicating responses to cellular signals.