Star fish do not have feet like we do but yet they do get about. So, how do they manage to move about you may wonder… well, they creep slowly around using hundreds of hydraulically operated ‘tube feet ‘ . Rows tiny tubes cover the length of each arm of a star fish. Each tube foot is connected to a muscular sac embedded inside the arm of the star fish. All the feet are joined up by a system of tubes which draws in water from the sea. The sac contracts & pushes out the foot under pressure. A suction disc at the end grips the sea floor, the foot contracts, forcing the water back in to the sac, and the star fish moves a fraction of an inch! Star fish can have between four to fifty arms. They lives in the shallow seas of the world.
(Junior Observer-2005)
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