Echinoderms and Urochordates

1. Echinoderms and Urochordates Alicia Jones Lakeisha Partridge Brittini Derickson

2. Taxonomy: Kingdom: Starfish are animal that really do move! Phylum: Echinoderm One of the characteristics of echinoderms is the presence of essentially tiny bones in the skin. Groups such as sea cucumbers are reduced or absent. Echinoderms also are characterized by a water vascular system. All echinoderms are pertaining to the sea, living in the ocean. There are 7000 living species of echinoderms. Class: Starfish Are starfish. There are 1500 living species of Asteroids. Order: The are seven orders of echinoderms, such as extinct groups of sea stars, tube feet lack suckers and so on. Family : There are also 11 members of the echinoderms family.

3. Systematic In traditional taxonomy, there are six classes of living echinoderms: Sea Lilies (crinoids) Starfish (sea star) Sea Urchin Sea Cucumber Sand Dollar Brittle Stars Fossil echinoderms were much more diverse in form than living ones. Many of the had very unusual morphologies

4. Habitat Cobbles and boulders Gravel and sand offshore Burrowed mud Living organisms like sponges, anemone, and sea squirts Dead mollusks shell deposits Muddy sand and gravel Tropical habitats and cold sea floor Lagoons and bays

5. Body Structure Upper portion: the arm and the anus Bottom portion: mouth, jaw, arm furrow, two feet Water vascular Arms= the body plan has a 5 part symmetry however some echinoderms has up to 50 arms Reproduction: sexual reproduction is complicated starfish may reproduce sexually or asexually, fertilization is external, female releases millions of eggs Embryo->blastula->larva->many starfish has three or four arms after 6 months starfish are considered to be mature

6. Ecological Roles Echinoderms have many different types of lifestyles.� Some echinoderms such as starfish are predators, some such as sand dollars feed on detritus, and sea urchins scrape algae from the rocks.� Many echinoderms help to regulate the growth of seaweed which essentially help the growth of coral.�Echinoderms are essentially going to feed on anything that is too slow to escape.�Echinoderms do not have many predators due to their spiny shell and their lack of nutrients. Some of their predators are fishes, crabs, sharks, crows and other larger animals in the ocean.� The predator must be strong enough to break their shell.� Some predators, for example ducks, drop echinoderms until their shell breaks and then they eat them.�There are several ways that echinoderms protect themselves.� The first is that they have spines on their shell and sometimes even poisonous organs that can be harmful to animals as large as humans.� Secondly echinoderms may have chemical secretions that will cause other animals to respond by leaving them alone.� One type of chemical secretion is when a sticky mass from their anus that causes predators to become trapped.� Echinoderms also produce a toxin that may be lethal. Echinoderms tend to live in large numbers.� This has also been shown to have been true in the past from the fossil records.� Scientist believe this to be true for of a number of reasons.� First, the availability of food is greater in some areas which attracts more echinoderms.� Secondly, this may be due to a greater defense against predators.� It is also possible that this is an example of a social behavior in echinoderms.

7. Fun Facts 1,800 to 2,000 species are living in the ocean Life span up to 35 years No brain No blood No ears, nose, or eyes Echino means spiny, derma means skin Stomachs emerge from their mouth and ooze inside the shell Related to sea urchins and sand dollars Diverse feeding patterns, they are carnivores

8. Human Impact Are considered a food source to many countries Are used in soups which happens mostly in Asia Raw and cooked sex organs of sea urchins are considered to be a delicacy in Europe They produce a toxin called Holothurians, which can kill fish by poisoning waters, however it is not harmful to humans but beneficial in a way that may reduce the growth of certain types of tumors They are easy to collect and used to conduct research in developmental Biology They damage many coral reefs, they eat a lot of seaweed that is used commercially As predators one victim is Mollusks that cause severe damage to oyster beds

10. Urochordates Taxonomy Phylum is Chordate because when juveniles their rod structure (notochord) later matures into a backbone Three classes: Ascidiacea, Thaliacea, Larvacea Urochordates are known as sea squirts or tunicates Urochordata means �tail-cord�

11. Key Characteristics Urochordates are known as sea squirts or tunicates Urochordata means �tail-cord� Sea Squirts Habitats are often in shallow waters and attach themselves to hard objects like rocks Feeds on plankton that floats in the seawater Hermaphrodites Over 20 species found Size range from 0.1cm to 6 cm Brightly colored Body structure is mainly the smooth, wrinkled, or slick Upper portion- 2 openings one used to drink water, the other is used to dispense water from the mouth.

12. Video Link http://video.google.com/videoplay?docid=-1067581086327048501&q=Echinoderms&pr=goog-sl&hl=en