Phylum Porifera (Sponges) General Characteristics.

hylum Porifera are the lowest multicellular animals belonging to the kingdom Animalia. The word “Porifera” mainly refers to the pore bearers or pore bearing species. Based on the embryological studies, sponges are proved as animals and are classified into a separate Phylum in animals. The poriferans have a spongy appearance and are therefore called sponges. Characteristics of Phylum Porifera Some of the important characteristics of phylum Porifera are mentioned below. The cells of Poriferans are loosely organized. They are mostly found in marine water. Only a few are found in freshwater. They are asymmetrical. They have no organs in their body. They depict cellular grade of organization. The body comprises numerous pores known as Ostia and osculum. The central cavity is called spongocoel or atrium which opens to the outside through the osculum. They reproduce asexually by budding, and fragmentation. The nutrition is holozoic. They have the power to regenerate the lost parts. The exchange of respiratory gases and nitrogenous wastes occurs by the process of diffusion. #sponges