(biochemistry) A structure of a biological molecule in which there is a precise sequence or order of monomeric units. It serves as the covalent backbone of biological molecules (such as DNA and proteins).
For instance in proteins, there are four recognized levels of protein structure: primary structure, secondary structure, tertiary structure, and quaternary structure.
A primary structure of a protein refers to the linear sequence or order of amino acids (a polypeptide) during the process of protein biosynthesis or translation. The primary structure of a protein determines how the protein will fold into a more advanced structure, such as the unique three-dimensional structure of protein.
See also: protein structure