What are some functions of the epithelium?
The epithelial tissues can perform covering, impermeability and protection against the environment, for example, in the skin, resorption, as in the guts and renal tubules, gas exchange, for example, the amphibian skin, thermal regulation, like sweating, secretion of substances, as in the epithelium of glands. In some animals the skin also has the important function of camouflage and mimicry .