Members of the class Holothuroidea have elongated bodies along with leathery body walls. When disturbed, cuvierian tubules are released from the anus, which stick to the predator and allows the sea cucumber to escape.Their respiratory trees accomplish gas exchange. In addition to that, they are also deposit or suspension feeders, and they use oral tentacles in order to feed themselves. Other species eviscerate - release some internal organs through anus or mouth, and it regenerates lost body parts.