Demosponges is a class that contains most of the sponges.The difference between these kinds is in how their skeleton is made. Some types of cell in their outer layers may move into the middle layer and change their functions. Their middle jelly-like layers have many different types of cells. Like cnidarians (jellyfish, etc.) and ctenophores (comb jellies), and unlike all other known metazoans, sponges' bodies are made of a non-living jelly-like mass sandwiched between two main layers of cells.Most cells in its body can move around a few cells can even change from one type of cell to another. A living sponge can change the shape of its body.A few things make them different from other animals. Yes: inter-cell connections basement membranes No, except that Homoscleromorpha have basement membranes. Animals that get food this way are called filter feeders. Most sponges filter (take out) little bits of food from the water going through their bodies.

The water goes out through a big tube in the center. All sponges take in water through pores (little holes) in their bodies. There are more than 10,000 species of sponge. Most of them feed on bacteria and other microorganisms. Their bodies are full of pores and channels allowing water to circulate through them. The basic body plan is a jelly-like layer sandwiched between two thin layers of cells.

Nevertheless, sponges are quite successful. A sponge is an animal that grows in one spot like most plants do.

It is sessile: it cannot move from place to place the way most other animals can. It is a simple animal with many cells, but no mouth, muscles, heart or brain. For sponges used for washing, see Sponge (tool).Ī sponge is a member of the phylum Porifera.

Can some sponges move