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Diversity of Radiata. Casey, Brigid, Dory, Lawrence, Jess. Phylum Ctenophora. do not produce nematocysts (but can have them from eating Cnidaria) have comblike plates of cilia they use for locomotion mainly free swimming with some creeping and sessile forms about 150 species. Anthozoa.
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Diversity of Radiata Casey, Brigid, Dory, Lawrence, Jess
Phylum Ctenophora • do not produce nematocysts (but can have them from eating Cnidaria) • have comblike plates of cilia they use for locomotion • mainly free swimming with some creeping and sessile forms • about 150 species
Anthozoa Corals: -Soft Corals: sea whips, sea fans and gorgonians. Colonial polyps. Skeletons of CaCO3 spicules/ tough protein sheath. 8-sided symmetry. Gastrovascular cavity divided into units of 8. -Hard Corals: “reef builders”. Skeleton is CaCO3. Gastrovascular cavity split into multiples of 6 parts. Colonial polyps. Sea Anemones: -Gastrovascular cavity also split into 6 parts. Polyp stage. Have stinging cells. More than 1000 species found throughout the world.
Cubozoa • Similar to scyphozoans, but have a box-like medusa body • Four evenly spaced tentacles (Carybdeids) or four bunches of tentacles (Chirodropids) • Well-developed eyes and vision • Velarium- helps the jellyfish move more rapidly • 20 known species, found in mostly tropical and semitropical waters
Hydrozoa • Marine and colonial (in form) • lifecycle: • Asexual polyp & sexual medusa stages • Exceptions to exist • Freshwater hydrozoan: • Solitary polyp • mouth: hypostome-surrounded by tentacles that extend • chemical activator= glutathione causes mouth to open • Asexual budding- outpocketing from body wall • Hydroid Colonies: • Medusa stage • has base, stalk, and one or more terminal polyps • Mouth- end of suspended manubrium leads to a stomach and four radial canals • Other Hydrozoans • Siphonophores- floating colonies • hydrocorals-secrete massive calcareous skeletons that look like true corals
Scyphozoa • -A very broad class that includes some of the largest jellyfish ranging up to 3 meter diameter. • -Scyphozoa derives from the greek word for “drinking cup” • -Has two life stages: Sedentary polyps, and planktonic medusae which mature into adult jellyfish. • -Medusa of the class Scyphozoa have no velum unlike many other Radiata.
Class Staurozoa • life cycle does not include a medusa phase • structure • solitary polyp is stalked and attaches to seaweed and other objects on the seafloor using an adhesive disk • top of polyp has eight arms ending in tentacle clusters • polyps reproduce sexually • all marine