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 '
Is There a Doctor in the Mouse? right and eats the cake one layer at a time, then he takes the cherry on top. Tom sees this and mutters somewhat in the vein of, "Why, that mouse is very strong!" Afterwards, Tom sets up a mousetrap sandwich for Jerry. Jerry does take the bait, but doesn't trigger the trap. After Tom triggers the trap from attempting to bite Jerry, Tom yells in pain upside the light fixture! When Jerry takes a banana from the refrigerator, Tom grabs the banana and peels the skin, Jerry taunts him by kissing his nose then runs off. The effects of the