Milady Cosmetology Practice Exam 2025 – All-in-One Guide to Master Your Cosmetology Certification!

Coarse hair is generally recognized as the most resistant to chemical services. This resistance is due to the structure and density of coarse hair, which contains a thicker cuticle layer. The cuticle is the outermost layer of the hair shaft, and its thickness makes it more difficult for chemical solutions, such as those used in perming or coloring, to penetrate effectively. As a result, when applying chemical treatments to coarse hair, professionals often need to adjust processing times, formulations, or methodologies to achieve the desired outcome, as the hair will not readily absorb the chemicals as finer or more porous hair types might.

In contrast, fine hair has a thinner cuticle, which can make it more susceptible to damage from chemical services but allows for easier penetration of solutions. Medium hair presents a balance between fine and coarse, exhibiting moderate resistance to chemicals. Processed hair has already undergone chemical treatments, which can alter its structure and resistance, potentially making it more fragile and sensitive to further chemical applications. This distinction in hair types is crucial for cosmetologists when planning and executing chemical services to avoid damage and achieve the best results.