North Dakota Barber Practice Exam

What is the chemical process that changes the structure of hair during chemical relaxing?

1. Oxidation of the hair shaft

2. Breaking disulfide bonds

3. Hydrolysis of amino acids

4. Rearrangement of protein chains

The correct answer is: Breaking disulfide bonds

The chemical process that changes the structure of hair during chemical relaxing involves breaking disulfide bonds. Hair is primarily composed of a protein called keratin, which contains many sulfur-containing amino acids. These amino acids can form disulfide bonds that create the hair's strength and structure. During the chemical relaxing process, a relaxer is applied, which typically contains strong alkaline substances or reducing agents. These agents penetrate the hair shaft and cause the disulfide bonds to break. Once the bonds are broken, the hair's natural curl pattern can be altered, allowing for a straighter appearance. The significance of breaking disulfide bonds in this process highlights how chemical relaxing effectively changes the physical structure of the hair, providing the desired result of straightening. Understanding this process is crucial for barbers and stylists, ensuring they can carry out these treatments safely and effectively.