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Phylum Porifera- are sponges. Sponges have cellular-level organization, meaning that that their cells are specialized so that different cells perform different functions, but similar cells are not organized into tissues and bodies are a sort of loose aggregation of different kinds of cells. Sponges are found in virtually all aquatic habitats, although they are most common and diverse in the marine environment. Many species contain toxic substances, probably to discourage predators.

Phylum Chordata- This is our phylum. Characterized by vertebrates ( spine, dorsal hollow nerve cord)

Phylum Cnidaria- includes jellyfish, hydra, sea anemones, and corals. Cnidarians are radially or bi radially symmetric. They have achieved the tissue level of organization, in which some similar cells are associated into groups or aggregations called tissues, but true organs do not occur.

Class Hydrozoa- known as box jellyfish. Effective predators and strong swimmers, they feed mostly on fish. Their nematocysts(stingers) are especially potent, sometimes resulting in the death of unfortunate human swimmers who encounter them.

Class Anthozoa- includes a variety of animals that have polyps with a flower-like appearance such as sea anemones and corals. The appearance is usually in a biradially symmetric pattern.

Order Alcyonacea- The soft corals an order of marine coelenterates(includes the corals, all the jellyfish and their allies and the comb-jellies. ). They consist of a firm mass, throughout which calcareous spicules are dispersed. The surface is studded with hydralike polyps with tentacles. They are found attached to rocks and seaweed.

Order Gorgonacea- Sea fans, Order Gorgonacea, are colonial Anthozoans anchored on hard substrates, supported by an internal, central horny/wood-like skeleton. They're colonies are covered by a thick "rind-like" skin. Unlike anemones, but like corals, sea fan...