Natural fiber Keratin is a structural protein located at the hard surfaces in many vertebrates. Keratin has two forms, α-keratin and β-keratin and are used by different classes of animals. The naming convention for proteins follows that for keratin, alpha keratin is helical and beta keratin is sheet like. Alpha keratin is found in mammalian hair, skin, nails, horn and quills, while beta keratin can be found in avian and reptilian species in scales, feathers, and beaks. The two different structures of keratin have dissimilar mechanical properties, as seen in their dissimilar applications. The relative alignment of the keratin fibrils has a
Hair removal Justice, its highest governing body. Sikhs take an even stronger stance, opposing all forms of hair removal. One of the "Five Ks" of Sikhism is Kesh, meaning "hair". To Sikhs, the maintenance and management of long hair is a manifestation of one's piety. Under Muslim law (Sharia), it is recommended to keep (the beard), and that which is the object of recommendation (foot, hand, back, and chest hair). A Muslim may trim or cut hair on head. The hairs on the chest and the back may be removed. In the 9th century, the use of chemical depilatories for women was