Mollusks

3. made of calcium carbonate secreted by the mantle, found in snails, bivalve mollusks, chitons, and nautilus.
5. A small hole in the side of the body, used for breathing-in gastropods.
7. burrow through wood, including docks and ships.
8. Protective covering that may or may not form a hard calcium carbonate shell.
9. contains digestive, circulatory, respiratory, and reproductive internal organs.
13. this mollusk class includes snails and slugs.They are the largest of the classes, can be marine or terrestrial, the shell is always univalve, and the apex contains oldest and smallest whorl.

1. most have a closed circulatory system with a heart, blood vessels, and capillaries
2. How bicalces feed.
4. the space between the mantle and the visceral mass where the respiratory organs are generally housed.
6. this mollusk class includes chitons.They have 8 overlapping plates, can roll up, live mostly in rocky zones, have gills, and use radula to scrape algae off of rocks.
8. used for movement which is modified into tentacles for squid and octopus.
10. this mollusk class includes octopus and squid. They are buoyant due to a series of gas chambers, are carnivores, swim by expelling water from mantle cavity.
11. this mollusk class includes clams, muscles, and oysters.They have two shells, mostly sessile, no head or radula.
12. They have defense mechanisms and are highly intelligent. They can change color, use jet protrusion, and produce and inky substance.