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Sponges and Key words Porifera cnidarian poriferan soft

Sponges (Phylum Porifera) c glass sponge ● Sponges are a group of very simple . They are also known as poriferans after their phylum Porifera. There are about 10,000 , most of which are marine, though a few are freshwater. ● They range in size from a fraction of an inch (a few mm) to 6 feet (2 m). ● They have no , muscles, or a sponge internal organs, and consist essentially of a body cavity connected to the exterior by pores. ● Sponges are filter feeders: flagellated collar cells line the body cavity and are used to create currents that b horny sponge draw in and food particles. ● Four classes of sponge are recognized, based on structure and composition of Cnidarians the : Phylum Cnidaria Calcare (a); class Demospongiae (b); class Hexactinellida (c); class Sclerospongiae (rare).

Cnidarians (Phylum Cnidaria) ● Cnidarians are a group of simple d animals that include anemones, jellyfish, hydras, and . ● There are about 9,400 species: most are marine, but a few live in freshwater. ● They are radially symmetrical with a , simple sensory organs, and a . f soft coral ● They have one of two basic body : () or medusa. ● They capture prey items using and nematocysts (stinging cells). ● There are four classes of cnidarians: class (hydroids); class (true jellyfish) (d); class (sea anemones, e, and corals, f); class Cubozoa (sea wasps and ).

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