Porifera
*Classification*- Sponge
- The approximately 5,000 living sponge species are classified in the phylum Porifera, which is composed of three distinct groups, the Hexactinellida (glass sponges), the Demospongia, and the Calcarea (calcareous sponges).
Main Structures- Porocyte - doughnut shaped cells that allow water to enter the sponge
- Choanocyte - flagellated cells that line the interior of the spongocoel
- Spicule - Spike shaped structure made of calcium
- Osculum - larger opening where water flows out of the sponge