1. Phylum Mollusca “soft- bodied”

2. 4 Primary Classes –Class Gastropoda: Snails, conchs, slugs, sea slugs, sea hares, limpets, etc. (very diverse)

3. Gastropoda: “stomach-footed” Snails and slugs

4. Class Bivalvia: Clams, oysters and scallops

5. Bivalvia: “two halves” Clams, oysters, scallops, mussels

6. Class Cephalopoda: Octopi, squid, nautilis, cuttlefish

7. Cephalopoda: “head-footed” Octopi, cuttlefish, squid, nautali http://www.youtube.com/watch?feature= player_detailpage&v=YVvn8dpSAt0

8. Blue-Ring Octopus

11. Cuttlefish

13. Squid

14. Giant Squid Avg. length: 35 feet Max. Length: 80 feet

15. Colossal Squid Maximum length: 43 feet

16. http://www.ted.com/talks/david_gallo_ shows_underwater_astonishments.html

17. Class Polyplacophora: Chitons

18. Body plan Bilateral Symmetry Muscular foot used for locomotion, burrowing and capturing prey Mantle, an outgrowth of tissue that covers most of it’s body. This secretes the shell. Coelom -Body cavity primarily around heart Shell - Made of calcium carbonate, internal or external Viceral mass – the internal organs

19. Feeding Complete digestive system Herbivores use a radula to scrape algae from rocks Carnivores use jaws to eat prey like the octopus Filter feeders use a siphon to catch plankton

20. Gas exchange via gills, lungs Land snails respire through a mantle or its body surface Respiration

21. Open circulatory system- except cephalopods, where the blood is transported through the body via a cavity called the hemocoel Leaving the vessels, blood travels through sinuses or large sack-like spaces Possess blood vessels by a heart Fast moving mollusks have a closed circulatory system using blood vessels Circulation

22. Excretion Tube shaped nephridia remove ammonia from the blood and release it outside the body

23. Response Nervous system varies greatly. Other than cephalopods, it is very basic. Several ganglia in clams and bivalves Cephalopods have a highly developed brain and nervous system, near equal to vertebrates.

24. Movement Some secrete mucus Others like the octopus move by jet propulsion

25. Reproduction Reproduction is sexual by external fertilization as in snails and bivalves Some are hermaphroditic like the snail

26. Ancestry of Molluscs

27. Phylum Significance Eaten for food by humans and other animals. Clams, oysters, scallops, mussels, (shellfish) snails (escargot), octopus and squid are popular foods Research - i.e. snails appear to be cancer free Indicators of environmental pollution Land snails and slugs damage gardens and crops Shipworms destroy wooden boats, docks, and piers. Filter feeders can concentrate toxins through biological magnification (Humans eating them can become ill or even die).