They are a unique group as they have 5-rayed symmetry or pentametry which extends to all members of the group though may be multiplied to 10, or 15 or more. Quizlet is a free service that allows you to create, edit, and share your own online flashcards for studying any topic. There are over 6,000 species. Open circulatory system and lack a brain. In these animals, water enters through a structure called the madreporite, passes through channels and reaches the ambulacral feet along the undersurface of the body. They can be found in the ocean from the equator to the poles. The sea cucumber can move, so it can search for its food. There are roughly 6000 living species of echinoderms. The sea lily is anchored to the sea floor. Using their water vascular system by pushing out and pulling in its tube feet. This is a system of fluid filled, closed tubes that work together to enable echinoderms to move and get food 2. 8-10 tentacles . They do not need to be able to stand up straight like we do. Sea urchins and sand dollars are found in all the world's oceans. What do starfish eat? They also have a water vascular system that acts as a circulatory system. Contents of Water Vascular System 3. Introduction to Water Vascular System 2. Quickly memorize the terms, phrases and much more. The podia can also be used to hold on to the substrate, small stones for protection, or a number of objects to use as camouflage. True. Describe Echinoderms . Echinoderms are radially symmetrical animals that are only found in the sea (there are none on land or in fresh water).Echinoderms mean "spiny skin" in Greek. How to Create a Set in Quizlet. ... Their tube feet allow them to move about slowly looking as if they are walking on stilts. At Unilever we meet everyday needs for nutrition, hygiene and personal care with brands that help people feel good, look good and get more out of life. Adults of the echinoderms are easily recognizable by the pointed radial symmetry. Bulb connected to tube feet that are extended by water squeezed from muscles in the feet; has a sucker for attachment. Many echinoderms only show themselves at night (= nocturnal), therefore reducing the threat from the day time predators. Echinoderms are spiny skinned invertebrates that live in the Ocean. muscles. Instead, they have a water vascular (otherwise known as "ambulacral") system, made up of a network of canals to move water. They are among the most distinctive organisms within the animal kingdom. They are usually found in ocean depths from the intertidal zone to the abyssal zone. STUDY. sea cucumber. This quiz has been developed to test your knowledge about different species which belong to Phylum Echinodermata. Echinoderms are animals that belong to any member of the phylum Echinodermata. How do echinoderms move. This includes animals such as sea stars, sea urchins, and sand dollars. But they are still preyed upon by shells (like the triton shell), some fish (like the trigger fish), crabs and shrimps and by other echinoderms like starfish which are carnivorous. This means they do not have a back bone. True of False: Echinoderms have Radial Symetry. General Plan 4. Echinoderms Echinoderms. What type of circulatory system do echinoderms have . Starfish, Sea Urchins, Sand Dollars, and Sea Cucumbers. Echinodermata. Can echinoderms regenerate. The system that allows echinoderms to move and to attach to substrates is called the ambulacral system.