Describe the structure of protein molecules in terms of their functions.

The basic building blocks of proteins are amino acids, which are small organic molecules that are made up of an alpha (central) carbon atom bonded to an amino group, a carboxyl group, a hydrogen atom, and a variable component called a side chain. Within the protein, numerous amino acids are linked by peptide bonds, thus forming a long chain. Peptide bonds are formed by a biochemical reaction that extracts a water molecule. Proteins are built from a set of twenty amino acids, each with a unique side chain. The primary structure of a protein is its amino acid sequence – and it leads to the folding and intramolecular binding of the linear amino acid chain that ultimately defines the protein’s unique three-dimensional shape.