RNA, or ribonucleis acid, is a kind of nucleic acid along with DNA. Both are composed of one nitrogenous base, one phosphate molecule, and one sugar. The difference between the two, is that in DNA, the sugar is deoxyribose, where in RNA, the sugar is ribose. Also, among the four bases, adenine (A), guanine (G), and cytosine (C) are common, but thymine (T) in DNA is uracil (U) in RNA instead, helping to compose proteins. There are several kinds of RNA, including messenger RNA, transfer RNA, and ribosomal RNA.
Unlike DNA, RNA do not have a double helix structure.
Messenger RNA transfers the information of the kinds and amount of amino acids when in protein synthesis proteins by serving as a template of DNA.
Transfer RNA transfer amino acids to ribosomes when in protein synthesis. There are 20 kinds of amino acids to compose proteins, and for each amino acid, there is a transfer RNA that corresponds with it.
Ribosomal RNA creates ribosome molecules in which protein synthesis takes place.