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ECHINODERMS. SAND DOLLARS. General Characteristics of Echinoderms. They have tubed feet . They use them to move and to grasp food . . They have a water based vascular system which circulates water through their bodies and helps c ontrol their movement . . Most but not all have
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GeneralCharacteristicsofEchinoderms Theyhavetubedfeet. Theyusethemtomove and tograspfood. Theyhave a water basedvascular system which circulates water throughtheirbodies and helps controltheirmovement. Mostbutnotallhave Radialsymmetry: five or more arms radiatingfrom a central body. Mostechinoderms can regenerate (re-grow) body parts.
What and how do theyeat? Seacucumbersusespecialisedtentaclescalledfeedingtentaclestopick up debristhatfallsto the seafloor. They are referredtoas ‘vacuumcleaners’. Starfishfeed on sponges and mollusks, evensand dollars. Theyhave no hard mouth part. Theyextrude theirstomachovertheirprey. Digestive juices are secreted and the tissueofpreyliquefied. The digestedfoodissucked in.
Seaurchinseatmainlyplantmatterlikealgae. The mouthisclawlike and hasfivesharptooth-likeplates.