Louisiana State Board Cosmetology Gold Book Practice Test

The part of the hair that extends above the skin surface—the hair shaft—is made up of three layers: a outermost cuticle of overlapping flat cells, a middle cortex that provides strength, elasticity, and color, and an innermost medulla that can be a loosely packed core or may be absent in very fine hair. The epidermis and dermis are skin layers, not hair shaft components, the nail plate is part of the nail, and the follicle is where hair grows rather than the shaft itself.