1. 4/25/13 Objective: Phylum Cnideria DO NOW: Which term below can best be used to describe the relationship between the forearm of a cat and the forearm of an alligator? a. vestigial b. homologous c. analogous d. bottleneck

3. Phylum Cnideria (Hydra, Jellies, Sea Anenomies, Coral 2 Characteristics ALL Cniderians Share Tentacles with stinging cells Radial symmetry -No head -Body parts arranged like pieces of pie

4. Stinging Cells Cnidocytes: stinging cells along tentacles Nematocyst: type of stinging capsule -Coiled tubule with poisonous barb

5. Body Form Polyp: cylindrical body with tentacles coming from one end - sessile - ex: hydras Medusa: umbrella-shaped with tentacles around lower edge -Move freely -Ex: Jellies

6. Nutrition Tentacles: maneuver food into mouth in center Gastrovascular cavity: digestive sac - Fluid in cavity transport digested food to cells lining cavity, and transport waste out

7. Hydrozoa Hydras Some coral Portugese man-of-war Coloines of polyps

8. Scyphozoa Jellies

9. Anthozoa Sea anemones Most coral animals

10. Phylum Cnetophora Comb Jellies No stinging cells http://video.nationalgeographic.com/video/ player/animals/invertebrates-animals/other- invertebrates/jellyfish.html http://www.youtube.com/watch?v=u0I- 3wkH37w