End Show Slide 1 of 37 28–4 Echinoderms

End Show 28–4 Echinoderms Slide 2 of 37 Copyright Pearson Prentice Hall What Is an Echinoderm? Echinoderms are characterized by spiny skin, an internal skeleton, a water vascular system, and suction-cuplike structures called tube feet. Most adult echinoderms exhibit five-part radial symmetry.

End Show 28–4 Echinoderms Slide 3 of 37 Copyright Pearson Prentice Hall

End Show 28–4 Echinoderms Slide 4 of 37 Copyright Pearson Prentice Hall What Is an Echinoderm? The skin of echinoderms is stretched over an endoskeleton that is formed of hardened plates of calcium carbonate. Adult echinoderms typically have no cephalization. What Is an Echinoderm?

End Show 28–4 Echinoderms Slide 5 of 37 Copyright Pearson Prentice Hall Form and Function in Echinoderms Echinoderms have a system of internal tubes called a water vascular system. The water vascular system carries out many essential body functions, including respiration, circulation, and movement. Form and Function in Echinoderms

End Show 28–4 Echinoderms Slide 6 of 37 Copyright Pearson Prentice Hall Echinoderm Anatomy Form and Function in Echinoderms

End Show 28–4 Echinoderms Slide 7 of 37 Copyright Pearson Prentice Hall The water vascular system opens to the outside through a sievelike structure called a madreporite. Form and Function in Echinoderms madreporite

End Show 28–4 Echinoderms Slide 8 of 37 Feeding Echinoderms have several methods of feeding. Sea urchins use five-part jawlike structures to scrape algae from rocks. Sea lilies use tube feet along their arms to capture floating plankton. Sea cucumbers move across the ocean floor, taking in sand and detritus. Form and Function in Echinoderms

End Show 28–4 Echinoderms Slide 9 of 37 Copyright Pearson Prentice Hall Sea stars usually feed on mollusks such as clams and mussels. Form and Function in Echinoderms

End Show 28–4 Echinoderms Slide 10 of 37 Copyright Pearson Prentice Hall Movement Most echinoderms move using tube feet. Form and Function in Echinoderms

End Show 28–4 Echinoderms Slide 11 of 37 Copyright Pearson Prentice Hall Groups of Echinoderms Classes of echinoderms include sea urchins and sand dollars brittle stars sea cucumbers sea stars sea lilies and feather stars

End Show 28–4 Echinoderms Slide 12 of 37 Copyright Pearson Prentice Hall Sea Urchins and Sand Dollars Many are detritivores or grazers that eat large quantities of algae. Groups of Echinoderms

End Show 28–4 Echinoderms Slide 13 of 37 Copyright Pearson Prentice Hall Brittle Stars They are filter feeders and detritivores. Groups of Echinoderms

End Show 28–4 Echinoderms Slide 14 of 37 Copyright Pearson Prentice Hall Sea Cucumbers Most sea cucumbers are detritus feeders. Groups of Echinoderms

End Show 28–4 Echinoderms Slide 15 of 37 Copyright Pearson Prentice Hall Sea Stars Most sea stars are carnivorous, preying on bivalves. If a sea star is pulled into pieces, each piece will grow into a new animal, as long as it contains a portion of the central part of the body. Groups of Echinoderms

End Show 28–4 Echinoderms Slide 16 of 37 Copyright Pearson Prentice Hall Sea Lilies and Feather Stars Many modern feather stars live on coral reefs, where they catch floating plankton. Groups of Echinoderms

End Show - or - Continue to: Click to Launch: Slide 17 of 37 Copyright Pearson Prentice Hall 28–4

End Show Slide 18 of 37 Copyright Pearson Prentice Hall 28–4 The body plan of echinoderms is unusual in that adult echinoderms a.lack cephalization. b.lack a nervous system. c.lack cephalization and cannot move. d.lack radial symmetry.

End Show Slide 19 of 37 Copyright Pearson Prentice Hall 28–4 The larvae of echinoderms are a.not symmetrical. b.radially symmetrical. c.bilaterally symmetrical. d.spherically symmetrical.

End Show Slide 20 of 37 Copyright Pearson Prentice Hall 28–4 The water vascular system of echinoderms opens to the environment through the a.tube feet. b.siphon. c.madreporite. d.mouth.

End Show Slide 21 of 37 Copyright Pearson Prentice Hall 28–4 The crown-of-thorns sea star is a major threat to a.marine algae. b.coral reefs. c.sea cucumbers. d.bottom-dwelling fish.

End Show Slide 22 of 37 Copyright Pearson Prentice Hall 28–4 All of the following are echnioderms EXCEPT a.sea stars. b.horseshoe crabs. c.sea cucumbers. d.sand dollars and sea urchins.

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