What substances make up a protein chain?

The amino acids in a polypeptide chain are linked by peptide bonds. Once linked in the protein chain, an individual amino acid is called a residue, and the linked series of carbon, nitrogen, and oxygen atoms are known as the main chain or protein backbone.

Proteins are organic molecules composed of Carbon, Hydrogen, Oxygen and Nitrogen. Proteins are crated by linking together amino acids into protein links called polypeptide chains.

Explanation:

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