Keratin Keratin Keratin () is one of a family of fibrous structural proteins. It is the key structural material making up hair, horns, claws, hooves, and the outer layer of human skin. Keratin is also the protein that protects epithelial cells from damage or stress. Keratin is extremely insoluble in water and organic solvents. Keratin monomers assemble into bundles to form intermediate filaments, which are tough and form strong unmineralized epidermal appendages found in reptiles, birds, amphibians, and mammals. The only other biological matter known to approximate the toughness of keratinized tissue is chitin. Keratin derives from Greek ' from '
Role of skin in locomotion and intact during flight. Bats rely on skin on their wings to generate lift and thrust used in flight. Therefore, the structure of the bat wing skin is different from the skin of the bat body. Bat wing skin consists of two thin layers of epidermis with a thin layer of dermis/hypodermis located between the epidermal layers whereas the skin of the bat body consists of a single layer of epidermis with a thicker layer of dermis internal to the epidermis. Within the dermal and epidermal layer of bat wing skin, the connective tissue and muscle fibers provide the structural