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Published byLesley Powers Modified over 9 years ago
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Phylum Mollusca
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___________________ symmetry Body Cavity - ___________________ Body has three distinct regions –_________________ - central section, which contains the body's organs –____________ - Means “cloak” in Greek. Wraps around the visceral mass, secretes shell. Mantle cavity -space between mantle & visceral mass. –________________ - Ventral, muscular and prominent. Functions: –Locomotion - Bivalvia use to dig into sand –Securing food - modified into a tentacle in Cephalopods
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Digestive System _______________- rasping organ in Gastropods, Beak in Cephalopods All mollusks except Bivalvia have this structure. Used to scrape algae off rocks (Gastropoda) or as a weapon to puncture holes in prey (Cephalopoda) Has mouth, esophagus, stomach, intestine and anus. Digestive gland secretes ______________ into the gut.
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Excretory System __________________ wastes dumped into coelom. Cilia in nephridium cause fluid (wastes and nutrients) to move through nephridia. Nutrients are _________________; wastes empty into the mantle, then removed.
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Circulatory System __________________________ for all except Cephalopoda. ______________________ - Coelom - restricted to the region around the Dorsal Aorta.
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Respiratory System ___________ located in their mantle cavity ____________ beat continuously causing a steady stream of _________ to pass over the gills. Gills also trap ___________
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Nervous System Ring of ___________________ around esophagus Two sets of ventral ________________ Nerve fibers maybe quite large - ________ __________________, _______________ and ________________ receptors
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Reproductive System Male and female ___________________ fertilization
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Major Classes Class _____________________ Class _____________________ Class ______________________ Class ______________________
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Class _______________ - Snails and slugs Examples: ________________ - Sea slugs _________________ secretes hard protective ____________. Some don't have shell. All _________________ mollusks are in this class, but most members are __________. Terrestrial mollusks don't have ___________.
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Class Gastropoda - Snails and slugs Uses _________________ to scrape algae for food ______________ adapted for locomotion. It forms a slimy path then ungulates foot (wave like motion) ______________ are located on a pair of stalk like tentacles on the head
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Class ________________ - Clams, oysters and scallops Examples - ___________________________, Name means: bi - “______", valva - “_________________________" Edge of _______________ secretes a two part hinged shell. Composed of __________________________. Shell shows _________________ lines. No distinct ____________ region, but have a central ________________ above foot Most are _______________, exception scallops and shipworms. Most are __________________
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Class Bivalvia Nervous System- touch and ______________ _____________________ System _______________________ connect the two valves together. ________________________ used to dig into the sand and locomotion Nutrition - __________________________. Use a hollow tube called a ________________ to pull in water. Water is then drawn over the _________ then out the ___________________ siphon.
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Class Bivalvia Reproduction ______________, Most species have separate sexes, few hermaphrodites. Shed ________ and _________ into water. Fertilization is ______________. _________________ develops into a free swimming ____________________ larva. Teredo (_____________) - feeds on ______________ that it ingests
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Class _____________________ - chitons Shell is embedded in _______________ Mantle cavity has two lateral grooves on each side of body where gills are located. Use _______________ to scrap algae Reproduce __________________, Separate sexes
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____________________ feet) Invertebrate
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Cephalopods History appeared some time in the late ____________ several million years before the first primitive fish began swimming in the ocean Scientists believe that the ancestors of modern cephalopods (Subclass Coleoidea: octopus, squid, and cuttlefish) diverged from the primitive externally shelled Nautiloidea (Nautilus) very early - perhaps in the Ordovician, some 438 million years ago.
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Cephalopod Hist. cont Cephalopods were once one of the dominant life forms in the world's oceans Today there are only _______ or so living species of cephalopods (compare that with 30,000 living species of bony fish). However, in terms of productivity, some scientists believe that cephalopods are still giving fish a run for their money
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_____________________ __________ swimming predatory animals Extremely ____________________ Cephalopods foot is divided into tentacles –squid=____ tentacle –octopus=_____ tentacle –cuttle fish=_____or more tentacle
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Cephalopods distinct structures Cephalopods have large, well developed ________ that form images Tentacles are covered with _____________ for seizing and holding prey Cephalopods have a _________ like structure in their digestive tract called a ______________ for breaking down food Cephalopods mouth has two strong ______________ for tearing its prey apart. Cephalopod is fitted with a ____________ like structure that fills with water and ejects it acting like a ____________________________
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Cephalopods masters of deception Able to change _________________ Can expand and contract _____________ cells in its _________ _____________________(color cells) give the cephalopod the ability to change. Can eject _____ when alarmed causing the enemy to be temporarily blinded. The ink also inactivates predators chemical receptors used for detecting prey.
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Cephalopods Diet Feed on crabs, shrimp, fish, and other cephalopods
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Cephalopods Habitat ____________ to ___________ Polar to tropics In other words they are found __________________
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Giant Squid Giant squid get up to _____ feet (20 m) in length and easily hold the record as the ________________________________ Despite the size of these beasts no one has ever seen one alive in its natural environment Main Diet of the __________________ Giant squid were once mistaken for sea monsters in sailing days
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