Which type of bonds connect polypeptide chains side by side?

The correct answer pertains to the types of interactions that hold polypeptide chains together within proteins. Side bonds, specifically, refer to various non-covalent interactions, such as hydrogen bonds, ionic bonds, and van der Waals forces, which can stabilize the three-dimensional structure of proteins by connecting different polypeptide chains.

These side bonds play a significant role in maintaining the overall shape and function of proteins, allowing flexibility and dynamic changes in structure. They are distinct from covalent bonds, which form strong, stable connections between atoms or molecules within a single chain or between chains. Understanding side bonds is crucial in the context of chemical texturizing, as they influence the properties and behaviors of hair treated with chemicals.