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:

it's a nutrition food for pregnant mothers so they unborn child can get its nutrition that it needs to grow in to a healthy baby.

explanation:

and the mother is getting all of her nutrition and her calcium and vitamins .