Henry Guan, Akash Kashyap, and Angus Qian http://peterbe.mobi/plog/interior-octopus/octopus.jpg Akash Kashyap
Overview 85, 000 species Marine, Terrestrial, Freshwater habitats Very Diverse Classes: Chitons, Gastropods, Bivalves, Cephalopods Shelled cephlapods called ammonites http://biology.unm.edu/ccouncil/biology_203/images/protostomes/squid.jpg http://faculty.clintoncc.suny.edu/faculty/michael.gregory/files/bio%20102/bio%20102%20lectures/animal%20diversity/protostomes/lophotrochozoans/chiton_dorsal_surface.jpg http://www.manandmollusc.net/advanced_introduction/images/helix-pomatia1.jpg http://www.xconomy.com/wordpress/wp-content/images/2008/12/scallop_eyes.jpg http://www.environment.gov.au/biodiversity/abrs/publications/other/species-numbers/2009/04-02-groups-invertebrates.html#mollusca Akash Kashyap http://www.nhm.ac.uk/nature-online/virtual-wonders/ammonite/img0001.jpg
Body Cavity and Symmetry Mollusks have a coelom Cephalopod (Octopus, Squid) Exception Visceral mass contains organs Bilateral Symmetry http://bio1151b.nicerweb.net/locked/media/ch33/33_15molluscbodyplan-l.jpg http://www.museumeducation.bedford.gov.uk/bedfordbytes/nature/images_nature/gallery_natural_objects/images/scallop%20shell_jpg.jpg http://infusion.allconet.org/webquest/phylummollusca.html http://fractalontology.files.wordpress.com/2008/03/nautilus.jpg Akash Kashyap
Nervous System 2 main nerve cords, 3 in bivalves Visceral internal organs, Pedal foot Ganglia control rooms throughout body Cerebral ganglia = eyes interaction with brain, pedal ganglia = foot, commissures Brain, Cephalopod most developed http://infusion.allconet.org/webquest/phylummollusca.html http://faculty.vassar.edu/mehaffey/academic/animalstructure/outlines/mollusca.html http://www.oceanicresearch.org/education/wonders/mollusk.html Akash Kashyap
Circulatory System Open circulatory system Small coeloms surround heart and gonads Hemocyanin as oxygen carrier Atria of heart functions as part of excretory system http://www.esu.edu/~milewski/intro_biol_two/lab 11_mollusca/images/bivalve_circulatory.jpg http://www.biology.ualberta.ca/courses.hp/zool250/labs/lab07/loligo-circ-syst.gif http://en.wikipedia.org/wiki/mollusca Angus Qian
Digestive System Most Mollusks have a radula Cephalopods have a beak Mouths contain glands that produce mucus Cilia in the digestive system sort out particles in the mucus Large food particles are sent to the cecum http://static.howstuffworks.com/gif/octopus-mantle.jpg http://www.bio.miami.edu/dana/pix/ham.jpg http://www.seaslugforum.net/images/gut2.jpg http://en.wikipedia.org/wiki/mollusca Angus Qian
Excretory System Atria of heart filters waste in blood Waste sent to kidneys as urine Nephridia collect salvageable materials (return to body) and remaining materials released in urine Waste sent to mantle for expulsion Artia doesn t filter No Kidney like you see in us.. Use Nephridia (kidney precursor) http://en.wikipedia.org/wiki/mollusca http://webs.lander.edu/rsfox/rsfoximages2/bivalve142a_x550_x_413x.gif Angus Qian
Locomotive/Musculature All molluscs have a muscular foot In chitins, foot acts as a suction cup In bivalves foot is modified into a burrowing organ In cephalopods foot in used in jet propulsion Gastropods use the mucus produced in the mouth the mouth to slide along http://www.freewebs.com/adoptamollusk/organsystems.htm http://cas.bellarmine.edu/tietjen/laboratories/bio%20pix%204%20u/image95.gif http://en.wikipedia.org/wiki/mollusca http://www.palaeos.com/invertebrates/molluscs/images/mollusc_classes.jpg Angus Qian
Sensory Structures / Features Eyes Big and developed to small and basic Tentacles (Gastropods, Cephalopods) Touch, Smell Statocysts Balance Osphridia Mainly used to test incoming water Helps gills http://seawifs.gsfc.nasa.gov/ocean_planet/images/squid_radula.gif http://www.pirx.com/gallery/albums/mollusks/radula.jpg Henry Guan
Skeletal Type Mainly Exo-Skeletons Mantle excretes shell Chitin, Conchiolin, Hardened with Calcium Carbonate Squid s have a style, support Slugs, Squid, Octopuses lost shell during evolution http://www.worldzootoday.com/wpcontent/uploads/2009/03/aleqm5jnf mrfbli15mifyiejseclvsvdgg.jpeg Henry Guan
Reproduction Mollusks can be hermaphrodites, or dioecious Gonads in visceral mass Larval stage called trochophore Usually external fertilization (No Copulation) Can also go through mating rituals This involves copulation http://farm3.static.flickr.com/2418/2265118301_dbcd6bdfd8_o.jpg http://imgs.sfgate.com/c/pictures/2008/04/17/ba_octo1.jpg Henry Guan
Gas Exchange Gills Filmaents (cilia) help gills Osphridia also help No gills, gasses diffuse through mantle wall http://i14.tinypic.com/2emev07.gif Henry Guan
Unique Features Largest Eyes in all of Animalia Kingdom Colossal Squid! Up to 46 Feet Largest known Invertebrate http://photos.mongabay.com/07/0223cs2.jpg http://www.benjaminmccormick.com/imgphotos/smallsquid_eye_m.jpg Henry Guan
Quiz Questions What other system (no Circulatory) do the atria of the heart come into play with?
Excretory
What are the two main components of the mollusks exoskeleton?
Calcium Carbonate Chitin
What category in the mollusks do not have coelom?
Cephalopods
Fertilization for mollusks usually happens where?
External Fertilization Usually in the ocean/water