The Cnidaria phylum consists of 9000 different species of aquatic animals. The stingers of all cnidarians are used to capture prey. The majority of cnidarian species are not dangerous to humans. They tend to be symmetrical, and anemones resemble flowers but they have mouths. The two body types of cnidarians are called polypoid and medusoid. Polyploids have tentacles and mouths that face up, while the tentacles and mouths of medusoids face down.

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