What is a "sponge"?

A sponge is a simple multicellular organism that belongs to the phylum Porifera. They are characterized by their porous body structure, which is made up of numerous tiny openings called pores. Sponges can be found in a variety of marine environments, from shallow coastal waters to the depths of the ocean. They have a remarkable ability to filter water and extract nutrients from it using specialized cells called choanocytes. Sponges come in a wide range of sizes, shapes, and colors, with some species forming intricate and beautiful structures. They play important ecological roles by providing habitats and serving as filter feeders, helping to maintain water quality and biodiversity. Despite their seemingly simple appearance, sponges possess unique biological features and are a fascinating group of organisms in the marine ecosystem.