Protein Diagram. If you followed the protein chain all the way to its left hand end you would find an amino acid residue with an unattached nh 2 group. Proteins are composed of chains of amino acids.
For example the hormone insulin has two polypeptide chains a and b shown in diagram below. If you followed the protein chain all the way to its left hand end you would find an amino acid residue with an unattached nh 2 group. An organic compound that is made of one or more chains of amino acids and that is a principal component of all cells.
240 protein databank pdb file 1f88.
The insulin molecule shown here is cow insulin although its structure is similar to that of human insulin. Figure 1 protein structure. Proteins are organic nitrogenous compounds in which a large number of amino acids are joined together by peptide linkages to form long polypeptide chains. The refined rhodopsin structure is from ref.