What are the primary elements that compose proteins?

The primary elements that compose proteins are carbon, hydrogen, oxygen, and nitrogen. Proteins are macromolecules made up of amino acids, which contain a central carbon atom bonded to an amino group (–NH2), a carboxyl group (–COOH), a hydrogen atom, and a variable side chain or R-group that defines the specific amino acid.

Carbon is the backbone of amino acids, allowing for the formation of diverse structures. Hydrogen and oxygen are also integral to the structure of amino acids and contribute to various functional groups and chemical bonds within proteins. Nitrogen is a critical component of the amino group, making it essential for the formation of the peptide bonds that link amino acids together, forming the protein polymer.

Ultimately, the presence of these four elements is vital for the formation, structure, and function of proteins in all living organisms, enabling them to perform a wide range of biological activities, from catalyzing metabolic reactions to providing structural support in cells.