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Phylum Mollusca. The Mollusks. More than 110,000 described species Very diverse, including snails, clams, squid, etc Found in all environments and range in size from microscopic to huge. Mantle : thick epidermal sheet covering the dorsal side of the body, makes the shell
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Phylum Mollusca The Mollusks
More than 110,000 described species • Very diverse, including snails, clams, squid, etc • Found in all environments and range in size from microscopic to huge
Mantle: thick epidermal sheet covering the dorsal side of the body, makes the shell • Foot: used for locomotion • Radula: rasping, tongue-like structure used for feeding The Mollusk body plan is complex and varied
Gas Exchange: Most have gills, terrestrial species have primative lung • Circulation: 3-chambered heart with open circulation, closed circulation (veins and arteries) in Cephalopods • Excretion: Nephridia • Digestion/feeding: diverse with a radula, beak, or a siphon and filter. Digestive system is complete • Reproduction: sexual, some species are hermaphroditic. Many have a larval stage • Response to environment: Adapted to wide variety of habitats and feeding strategies, Cephalopods can shoot a cloud of ink to startle predators • Movement: muscular foot in most, jet propulsion in Cephalopods
Class Gastropoda: Snails and Slugs (“stomach-footed”) Kevin Lee http://imamook.wordpress.com www.kent.edu www.takingoff.org
Class Gastropoda: Snails and Slugs www.photec.co.uk
Class Bivalvia: Clams, mussels, and cockles (“two-valves”)
Class Bivalvia: Clams, mussels, and cockles (“two-valves”) www.nano-reef.com
Class Bivalvia: Clams, mussels, and cockles (“two-valves”) Unknown source
Class Cephalopoda: Squid, Octopuses, Cuttlefishes, and Nautiluses • “head-footed” Unknown source
Class Cephalopoda: Squid, Octopuses, Cuttlefishes, and Nautiluses Wallpaperden.com
Class Cephalopoda: Squid, Octopuses, Cuttlefishes, and Nautiluses David Harasti
Class Cephalopoda: Squid, Octopuses, Cuttlefishes, and Nautiluses Ingrid Taylar