Matching Pairs Hair CompositionOnline version Match the term to the sentence that the term completes. by Rosalind Carter 1 disulfide bond 2 hydrogen bond 3 lanthionine bond 4 side bond 5 salt bond Weak, physical, cross-link side bond between adjacent polypeptide chains, easily broken by strong alkaline or acidic solutions. Strong, chemical side bond that joins the sulfur atoms of two neighboring cysteine amino acids. Bond created when disulfide bonds are broken by hydroxide chemical hair relaxers after the relaxer is rinsed from the hair. Bond that cross-links the polypeptide chains together and is responsible for the extreme strength and elasticity of human hair. Weak, physical, cross-link side bond that is easily broken by water or heat.