The structure of a protein refers to the linear sequence of amino acids in that protein. Make up an example of the primary structure of a protein in the space below. The structure of a protein refers to the regular, recurring arrangement of the amino acid chain. One such arrangement, called the alpha helix, occurs when the amino acid chain forms a spiral coil. Draw an example of this structure in the space below. Another type of structure, called the beta sheet, consists of parallel strands of polypeptides. What types of bonds hold these sheets together? The structure of a protein refers to the specific folding and bending of the primary structure and secondary structure into coils or fibers. It is this structure that gives proteins their biological activity. In the space below, draw a representation of this level of structure. Some proteins have a structure that occurs when two or more peptides come together to form a more complex unit. In the space below, draw a representation of a protein that has a quaternary structure.