New York State Cosmetology Practice Exam 2026 - Free Cosmetology Practice Questions and Study Guide

The cuticle serves a crucial protective function for hair. It is the outermost layer of the hair shaft, composed of overlapping, scale-like cells that lay flat against one another. This layer acts as a barrier, shielding the inner structures of the hair, including the cortex and medulla, from environmental damage, chemical treatments, and physical wear.

By preserving the integrity of the inner layers, the cuticle helps prevent moisture loss and maintains the overall health of the hair. A damaged or compromised cuticle can lead to various issues, such as split ends, dryness, and increased susceptibility to breakage.

Understanding the role of the cuticle highlights the importance of proper hair care practices to maintain this outer layer’s health, which in turn protects the inner components of the hair.