Porifera

• Porifera means organs with holes. So, there are holes or ‘pores’ on the body of these organisms. Body pores are called “Ostia”.
• The ‘Ostia’ opens into a canal system having canals and chambers. The canal system is a filter-feeding system of sponges. It helps in circulating water throughout the body to bring food, water and oxygen.
• All the animals are sessile (fixed in one place).
• They have a cellular level of classification.
• They are mostly found in marine water. Only a few are found in freshwater.
• The nutrition is holozoic.

For example: Euplectella,  Sycon, Spongilla