Unformatted text preview: 1. Asteroidea-sea stars 2. Ophiuroidea-brittle stars 3. Echinodea-sea urchins 4. Holothurodea-sea cucmbers 5. Crinoidea-sea lillies B. Characteristics 1. Deuterostomes 2. Primary bilateral symmetry 3. Secondary pentaradial symmetry C. Synapomorphies 1. Tubular coeloms 2. Water vascular system (coelom) 3. Endoskeleton of calcium carbonate 4. Mutable connective tissue-contain endoskeleton ossicles , which are “hole-y” skeletal structures similar to how our skull is assembled-with mutable connective tissue , they have the ability to instantly lack a very limber/flexible spine so that they can become immobile for protection and they can stay like this for as long as they want....
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- Spring '08
- RNA, Crustacean, cilia, mutable connective tissue, A. Major Groups, Arthropoda A. Major