Milady Cosmetology Practice Exam

What type of chemical reaction occurs during the waving process to alter the hair structure?

1. Oxidation

2. Reduction

3. Neutralization

4. Hydration

The correct answer is: Reduction

The waving process, commonly included in the perming of hair, involves a chemical reaction known as reduction. This process alters the internal structure of the hair by breaking and reforming disulfide bonds, which are responsible for the hair's strength and shape. In reduction, specific reducing agents, such as ammonium thioglycolate, are used to break these disulfide bonds in the hair. Once the hair is in the desired shape, a neutralizing agent is applied to reform the disulfide bonds in their new configuration, effectively 'locking' the waves or curls in place. Understanding reduction is crucial in cosmetology because it helps professionals appreciate how the hair's natural structure can be manipulated safely and effectively for styling, leading to successful and client-satisfying results. The other options—oxidation, neutralization, and hydration—do not describe the primary chemical interaction that takes place in the waving process.