Minnesota Cosmetology State Practice Exam

The epidermis is not a layer of the hair because it is the outermost layer of the skin, not the hair. The medulla, cuticle, and cortex are all layers of the hair. The medulla is the innermost layer, the cuticle is the outermost layer that protects the hair, and the cortex is the middle layer responsible for the hair's strength and elasticity. Therefore, the epidermis is the only option that is not a layer of the hair.