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| Phylum Coelenterata (Cridaria) |
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| Sea Anemone |
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 Two layered body which is radially symmetrical. |
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 Aquatic in habitat which includes both fresh water and marine. |
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 The outer layer has tentacles armed with stinging cells cnidoblasts which can release venom into the victim. The inner layer encloses a body cavity called gastro vascular cavity. |
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 Animals in this group exist in two types of individuals called zooids- polyps and medusae. Polyps are fixed and lead solitary or colonial life , while medusae are free swimming. |
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 Alternation of generation takes place in colonial forms. Polyps and medusae alternate with each other during the life cycle. |
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 Reproduction is usually asexual i.e., by budding in the polyp form and sexual in medusa form. |
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 Exoskeleton made of lime is found in corals. |
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| Example: Hydra, Obelia, Aurelia, Metridium. |
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