Transcript Slide 1
ECHINODERMS CREATED BY: Chris, MacKenzie, Amelia General Characteristics Habitat • Marine-bottom of deep sea trenches, sand, rubble, and coral reefs Body Plan (symmetry) • They have a radial body plan Body Systems Digestive What do they eat? • Plants, animals, tiny bits of food found on ocean floor and in the water How do they get their food? They have a mouth Describe how a sea star eats a clam: they turn their stomach outside their body and use their feet to pry open the shell and insert their stomach into the clam and then secrete digestive enzymes Respiratory Describe the water vascular system including the tube feet: Tube feet are tiny filled tubes help gather food, and aid in their movement. They can be stretched out, have suckers in rows on the bottom of their feet. Circulatory • What is the role of the water vascular system in the circulation: it pumps water through the body functions in feeding and gas exchange Excretory • What kinds of waste do echinoderms produce? Liquid, and solid • Describe how these waste are eliminated from the body of an echinoderm: through the anus, and through the tube feet Response/Nervous • What is the nerve ring and a nerve net? • A nerve net is a group of nerve cells that make a tissue called a nerve net • A nerve ring is a central ring of nerves that branches into each of the arms • What type of sensory cells do echinoderms have? What does each detect? Eyespots- allows them to detect light Skeletal and Muscular (Movement) • Describe the skeleton of an echinoderm: • It has an endoskeleton, which is composed of individual plates called ossicles • How is the water vascular system involved in movement? Through their tube feet they stretch out their limbs and then use the suckers on the bottom of their feet to move across the ocean floor Reproduction Describe asexual reproduction in echinoderms: a star fish can asexually reproduce a arm is cut off with a piece of the nerve ring Describe sexual reproduction in echinoderms: males and females release their eggs, and sperm into the water. Describe the larvae of an echinoderm: Free floating larvae feed on plankton, they have bilateral symmetry until they mature into their adulthood Groups of Echinoderms • Sea Stars • The mouth lies underneath the body in the middle • Brittle Stars • Can have more than five arms, small disk and long thin arms • Sea Lilies and Feather Stones • Most ancient and primitive, mouth located on upper surface Groups of Echinoderms… cont. • Sea Urchins And Sand Dollars • Do not have arms, some are ball shaped • Sea Cucumbers • Can be short and wide or long and thin • No arms, mouth at one end, the mouths have tentacles • Sea Daisies • Disk shaped, no arms, and have tube feet Importance's of Echinoderms • To Ecosystem • They signify change in their environments, they do that by dieing. They are intolerable of change • To Humans • Fisher men often cut starfish up when found in or on nets, this causes the starfish to grow in mass numbers Bibliography Blaxland,Beth. Sea Stars.sea Urchins, and their Relatives. Philadelphia: Chelsea House Publisher, 2005 Johnson, George B. Biology Principles and Explorations. Austin, Texas. Harcourt classroom education company, 2001. Zubi, Teresa. “Echinoderms.” Inverebrates. 15 April 2008. 18 April 2008. <http:www.starfish.ch/reef/echinoderms.html>. Thanks for listening to our presentation!