Wikipedia:POTD column/May 27, 2006



Sea anemones are water-dwelling, filter feeding animals, closely related to coral and jellyfish. They are composed of a small sac, attached to the bottom by an adhesive foot, with a column shaped body ending in an oral disc which contains the mouth, surrounded by the tentacles with stinging cells. The tentacles contain neurotoxins, which serve to paralyze and capture the prey, which is then moved by the tentacles to the mouth for digestion inside a central cavity. Anemones tend to stay in the same spot unless they are unhappy with that location, or a predator is attacking them. In the case of an attack, anemones can uproot themselves and swim away to a new location.

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