Corolate structure and function of specific epithelium in body?​

Epithelial tissues line the outer surfaces of organs and blood vessels throughout the body, as well as the inner surfaces of cavities in many internal organs. ... Functions of epithelial cells include secretion, selective absorption, protection, transcellular transport, and sensing.

Source:

https://en.m.wikipedia.org/wiki/Epithelium

If the experiment was perfomed more then once and you get the same results