Starfish have a mouth and anus on their underside, with the top side usually displaying bright colors. Starfish eat by projecting their stomach outward over their prey, then liquefying the prey with digestive juices before sucking their stomach back in. Some starfish are carnivorous, and their typical prey includes sponges and mollusks. Other starfish are scavengers or specialized feeders. Some starfish, such as the crown-of-thorns starfish, are venomous and can injure people when touched or stepped on. Read more : http://www.ehow.com/list_6495584_five-classes-echinoderms.html |