Hydra
(Science: organism) genus of freshwater coelenterates (cnidarians). They are small, solitary and only exist in the polyp form, which is a radially symmetrical cylinder that is attached to the substratum at one end and has a mouth surrounded by tentacles at the other. They have considerable powers of regeneration and have been used in studies on positional information in morphogenesis.
Hydra (Science: organism) genus of freshwater coelenterates (cnidarians). They are small, solitary and only exist in the polyp form, which is a radially symmetrical cylinder that is attached to the substratum at one end and has a mouth surrounded by tentacles at the other. They have considerable powers of regeneration and have been used in..
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