1. Chapter 25 Mollusksand Segmented Worms Segmented Worms

2. Phylum Mollusca (“soft”) Includes snails, clams, oysters, squids & octopus

3. (Phylum Mollusca) Most live in salt water Most live in salt water Bilateral symmetry Bilateral symmetry Breathe through gills Breathe through gills

4. (Phylum Mollusca) Most have … Most have … –paired eyes –3 chambered heart - open circulatory system –1 or 2 shells –separate sexes - reproduce sexually

5. All mollusks have a modified foot

6. (Phylum Mollusca) Coelum - large central body cavity Coelum - large central body cavity Visceral organs (guts) - complete digestive system Visceral organs (guts) - complete digestive system

7. (Phylum Mollusca) Mantle - thin membrane; surrounds internal organs; secretes the shell Mantle - thin membrane; surrounds internal organs; secretes the shell Radula - file-like “teeth” found in the mouth of many Radula - file-like “teeth” found in the mouth of many

8. PHYLUM: ANNELIDA “Little rings” / Segmented worms Includes: Includes: –Earthworms –Sandworms –Leeches –Bristleworms Bilateral symmetry Bilateral symmetry Free-living Free-living

9. (PHYLUM: ANNELIDA) Some have eyespots Some have eyespots Some have eyes Some have eyes Most are hermaphrodites Most are hermaphrodites

10. (PHYLUM: ANNELIDA) Primitive heart - 5 aortic arches Primitive heart - 5 aortic arches Complete Complete digestive system Nephridia - eliminates wastes Nephridia - eliminates wastes

11. (ANNELIDS) Simple nervous system Simple nervous system

12. (PHYLUM: ANNELIDA) Setae - tiny bristles Setae - tiny bristles Clitellum - Reproductive band on earthworms Clitellum - Reproductive band on earthworms

13. Chapter 29 Echinoderms

14. Phylum Echinodermata (“spiny skin”) Includes sea urchins, starfish, sand dollars, sea stars, sea cucumbers, brittle stars Includes sea urchins, starfish, sand dollars, sea stars, sea cucumbers, brittle stars Serpent star

15. Crown starfish Sand dollar Brittle star Heart urchin Sea urchin All have a hard, spiny, or bumpy exoskeleton

16. (Phylum Echinodermata) Aquatic Aquatic Radial symmetry Radial symmetry Sea stars

17. Sea cucumber Sea urchin with a worm Sea urchin with feathery tentacles Sea urchins Simple nervous system (no head or brain) Simple nervous system (no head or brain)

18. (Phylum Echinodermata) Water vascular system Water vascular system Have a mouth and stomach Have a mouth and stomach Cells that detect light and touch Cells that detect light and touch

19. (Phylum Echinodermata) Reproduce: Reproduce: –Sexually - have separate sexes –Asexually - regeneration (replace missing parts)