Sponges have many pores, holes and channels in their bodies. The spongocoel is the internal cavity of a sponge. Food and oxygen are taken into the sponge through pores, into the s pongocoel . The osculum of a sponge is a large pore that allows water to flow out of the body of the sponge. Commercial bath sponges are made of the spongin skeleton fibers of a sponge with all living material removed.
Some sponges have hard, mineralized skeletons called spicules .