1. MR. FAIA 4/24/15 6 TH GRADE SCIENCE Mollusks

2. What are Mollusks? Mollusks are:  Invertebrates  Have soft bodies  Unsegmented bodies  Often have shells

3. What are Mollusks? Mollusks also have a mantle  Thin layer of tissue that covers organs Mollusks include clams, oysters, scallops, snails and octopuses

4. What are Mollusks? The mantle also produces another structure, what do you think is? How do most mollusks move? Where do most mollusks live?

5. What are Mollusks? Mollusks have bilateral symmetry Internal organs are all located in 1 area

6. What are Mollusks? All mollusks have a pair of kidneys  Removes waste produced by the cells What organ would most water dwelling mollusks have?  It allows them to breath underwater Many mollusks have a radula  Tiny ribbon of teeth that acts like sandpaper

7. REVIEW 1) Describe the body of a mollusk. 2) What covers the internal organs? 3) List and describe 3 organs found inside a mollusk. 4) Where can mollusks live? 5) What type of symmetry do mollusks have?

8. Early Mollusks Mollusks have been around about 540 million years Fossil shells were discovered in limestone rocks

9. Types of Mollusks 3 major groups of mollusks  Gastropods  Bivalves  Cephalopods

10. Gastropod Largest group Includes snails and slugs Snails have shells, most slugs do not Can be found almost anywhere on earth

11. Gastropod Can be herbivores, carnivores, or scavengers Snails can use their shell to escape predators or dry conditions

12. Bivalves Means “two shells” Includes clams, oysters, scallops, and mussels Shells are held together by hinges and strong muscles

13. Bivalves Bivalves do not have radula They are filter feeders  What other animal(s) have we talked about that are filter feeders?

14. Bivalves Bivalves use their gills to filter food Cilia on the gills move food into the mouth

15. Bivalves Most bivalves either stay in 1 place or move slowly as adults Clams and scallops are the exceptions

16. Bivalves Pearls are formed when sand or grit gets between the mantle and shell The mantle coats the grit

17. Cephalopods Include:  Octopus  Squid  Nautilus  Cuttlefish

18. Cephalopods Nautilus has a shell Squid and cuttlefish have a thin shell inside the body Octopus has no shell

19. Cephalopods All cephalopods have tentacles The tentacles have suckers that can taste and touch

20. Cephalopods Excellent Vision Very large nervous system  Largest brain of any invertebrate

21. Cephalopods All live in the ocean Swim by jet propulsion http://www.youtube.com/watch?v=AQL89ymGT_s

22. Review What characteristics do most mollusks have in common? List the 3 groups of mollusks. How do bivalves get food? Which cephalopod has a shell? How old are mollusks? Give 2 examples of each type of mollusk. What is a mantle? What is a radula?