Electrolysis Practice Exam 2026 – Comprehensive Test Prep Tool

The cortex is the part of the hair structure responsible for its color. This layer contains the majority of the hair's mass and is composed of elongated cells filled with keratin. Within these cells are melanin granules, which are the pigments that determine the color of the hair. There are different types of melanin: eumelanin (which can be brown or black) and pheomelanin (which ranges from yellow to red). The proportion and distribution of these pigments in the cortex will influence the overall shade and tone of the hair.

In contrast, the cuticle is the outermost layer of the hair shaft and primarily serves as a protective barrier. While the cuticle can affect the shine and texture of the hair, it does not contribute to its color. The medulla, found at the center of the hair strand, is often absent in finer hair and does not play a role in color either. The dermal papilla is found at the base of the hair follicle and plays a crucial role in hair growth and nutrition but is not involved in determining the color of the hair.