What layer of hair contains melanin pigment and is a fibrous protein?

The cortex is the layer of hair that contains melanin pigment and is primarily made up of fibrous proteins. This structure is essential for the hair's strength and elasticity. The presence of melanin in the cortex is what gives hair its color; the different types and amounts of melanin determine whether hair appears blonde, brown, black, or red. Additionally, because the cortex makes up the majority of the hair's structure, it plays a significant role in the overall texture and integrity of the hair.

Other layers, such as the cuticle, serve different purposes; the cuticle primarily protects the inner layers from environmental damage but does not contain melanin. The medulla, if present, is typically located at the center of the hair shaft, but its function and structure can vary significantly among different types of hair. The term "outer layer" is not a specific reference to any recognized structure in hair anatomy and can lead to confusion about the actual components involved in pigmentation and strength. Understanding these distinctions is crucial for hair professionals when providing services or treatments.