Mollusca is a phylum of invertebrate animals that live in both marine and terrestrial habitats. They have soft bodies that are often covered by a hard exoskeleton. There are three main classes of molluscs: Bivalvia which have two-part shells like mussels and oysters, Gastropoda which have a single coiled or flattened shell like snails and slugs, and Cephalopoda which are the most advanced with arms surrounding a large head, like octopuses and squid. Molluscs play important ecological and economic roles as a food source, in industries like pearl farming and button making, and as decorative and building materials.

1. MOLLUSCA Vania and Rolla Kingdom: Animalia Phylum: Lophotrochozoa

2. Characteristics Soft bodies Typically only consists of head and foot part Body often covered with hard exoskeleton Live in terrestrial mountain tops to the hot vents and cold seeps of the deep sea Size from 20 m long to microscopic size

3. Structure

4. Classes MOLLUSCA

5. Class Bivalvia (Pelecypoda) Bi = two Valvia = valves Bivalvia = have shells composed of two pieces of valves The valves are used to protect themselves from danger and allowing the animals to move in water by clapping the valves together

6. Lifecycle

7. Examples Mussels Oysters Scallops Clams

8. Class Gastropoda They have single shell or no shell Can be found in both salt or fresh water and on land More active and mobile than bivalves There is a concentration of nerve cells in the tentacles and at the anterior end In some animals, eyes are highly developed

9. Lifecycle

10. Examples Snails Whelks Abalone Slug

11. Class Cephalopoda Considered as the most evolutionarily advanced animals to be found among the invertebrates Has a large head, conspicuous eyes and a central mouth surrounded by arms They have well-developed brains, resulting in highly developed sensory system and predatory behavior

12. Lifecycle

13. Examples Octopus Squid Cuttlefish

14. Roles Food source Economic activities  pearl selling, seafood marketing, shells are used for button producing Decorative materials Building materials  shells of oyster are mixed with tar and used for road making un US

15. Sources http://www.blurtit.com/q631046.html www.ucmp.berkeley.edu/taxa/inverts/mollusca/mollusca.php infusion.allconet.org/webquest/PhylumMollusca.htm