Skin care and skin treatment

The skin contains mammals often hair, which in sufficient density is called fur. The hair mainly serve to increase the isolation that gives the skin but can also serve as a secondary sexual characteristic or as camouflage. On some animals the skin is very hard and thick and can be processed to generate the leather. The reptiles and fish have scales on their hard protective skin for protection and the birds have feathers hard, made entirely of B-Keratins hard. The skin snakes is not a strong barrier to passage of chemicals. A frog that sits in an anesthetic solution will quickly sleep.