cross section of hair dye science on white background.

aging anatomy biology biotin black breakage brond brown care color colour conditioner cortex cross cuticle damage dermal dermatology dry dye eumelanin follicle granule gray grey hair head human illustration isolated keratin medicine medulla melanin melanocyte nutrition old papilla pheomelanin pigment pigmented prevent problem protect red repair root salon scalp section shaft shampoo skin treatment vector vitamin white