1. Radiate Animals Cnidarians and Ctenophores

2. Radiates Are Eumetazoans

3. Radiates Radial symmetry Tissue level organization Two germ layers –Ectoderm and endoderm Nerve net (simple nervous system) Extracellular digestion

4. Radiate Phyla CnidariaCtenophore

5. Phylum Cnidaria Two forms –Polyp –Medusa Tentacles Nematocyst

6. Polyp and Medusa Forms

7. Class Hydrozoa Mostly colonial Polyp and medusa life cycle for most Hydra – non colonial polyp stage only Obelia – typical colony –Chiton exoskeleton –Extracellular and intercellular digestion

8. Hydra

9. Hydra Tissue Structure

10. Obelia Life Cycle

11. Gonionemus

12. Class Scyphozoa Larger jellyfish Not colonial No vellum Internal gastric pouches –Radial canals lead to ring canal

13. Aurelia Life Cycle

14. Medusa

15. Strobilia

16. Class Anthozoa Subclasses –Zoantharia – anemones, hard coral –Alcyonaria – sea fans (soft coral) –Ceriantipatheria – tube anemone, horny coral Polyp form, no medusa stage Partitioned gastrovascular cavity

17. Sea Anemone

19. Anemone Fish (Clown Fish)

20. Zoantharian Coral Calcium carbonate exoskeleton secreted externally from base Contain mutualistic zooxanthallae algae Live in colonies Hexamerous symmetry

21. Coral Polyps

22. Alcyonarian Coral Octomerous symmetry Colonial Can communicate with members of colony through tubes call solenia Endoskeleton composed of spicules and protein and secreted within mesoglea

23. Soft Corals

24. Phylum Ctenophora Comb Jellies Move using cilia –Comb plates Do not have nematocysts –Colloblasts capture food

25. Comb Jelly Tentacle

26. Comb Jelly Structure

27. Comb Jelly Cilia

28. Predatory Comb Jellies Approaching Prey

29. Predatory Comb Jelly Engulfing a Comb Jelly

30. Comb Jelly After a Meal