Keratin is a fibrous protein that is the primary component of hair and nails. It is also found in the skin, where it helps to provide strength and elasticity. Keratin is a type of intermediate filament, which means that it is a strong, flexible protein that can withstand a lot of wear and tear.
Keratin is produced by cells in the hair follicles and nail matrix. The amino acid sequence of keratin varies depending on the type of hair or nail. For example, the keratin in hair is different from the keratin in nails. Keratin is also responsible for the strength, flexibility, and texture of hair and nails.
