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