Alpha-keratin Alpha-keratin Alpha-keratin, or α-keratin, is a type of keratin found in mammals. This protein is the primary component in hairs, horns, nails and the epidermis layer of the skin. α-keratin is a fibrous structural protein, meaning it is made up of amino acids that form a repeating secondary structure. The secondary structure of α-keratin is very similar to that of a traditional protein α-helix and forms a coiled coil. Due to its tightly wound structure, it can function as one of the strongest biological materials and has various uses in mammals, from predatory claws to hair for warmth. α-keratin is
The dogs and the lion's skin The dogs and the lion's skin The dogs and the lion's skin is a fable ascribed to Aesop and is numbered 406 in the Perry Index. However, it is only found in a mediaeval Greek manuscript claiming to be a translation from the Syriac (Syntipas, Fable 19). The story relates how some dogs, finding the skin of a lion, began to tear it to pieces. Seeing them, a passing fox remarked, "If this lion were alive, you would soon find out that his claws were stronger than your teeth." The moral in the original commented that "the fable is for