MORE MOLLUSKS

VOCAB

RADULA TONGUE covered with

teeth unique to mollusks

Used to drill OR scrape food off surfaces

NO RADULA IN BIVALVES

Image from: http://www.wildsingapore.com/chekjawa/text/i900.htm#r

CHROMATOPHORES

Pigments in the skin that help organisms blend in with their surroundings

Image from: http://www.biosbcc.net/ocean/marinesci/03ecology/mlimg/mlpop.jpg

COELOM = body cavity In organisms with OPEN CIRCULATION

coelom contains circulatory fluid (blood) = HEMOCOEL

Blood = HEMOLYMPH

Image: http://fig.cox.miami.edu/Faculty/Dana/ham.gif

CLAMS

Strain food from water =

FILTER FEEDERS

Clams stay in one place = SESSILE

http://www.cinderzelda.com/czpics/potato2.jpg

http://www.4discountcookware.biz/market/15189

MARINE/FRESH WATERMARINE – live in salt water

FRESH WATER- live in ponds, lakes, streams, rivers, etc.

Image: http://www.belizeanjourneys.com/grc/mangrove/man2.jpg

TROCHOPHORE LARVAFound in all

AQUATIC mollusks EXCEPT CEPHALOPODS

http://www.mbari.org/seminars/2003/summer2003/august4_rouse.html

http://www.okc.cc.ok.us/biologylabs/Documents/Evolution/Trochophore_larva.htm

TORSION in Gastropods

Twisting of body 180° during development

http://shells.tricity.wsu.edu/ArcherdShellCollection/Illustrations/TorsionStages.html

Clam from: http://www.geocities.com/TheTropics/2428/directory.html

CLASSES of MOLLUSKS

BIVALVES

Clams, oysters, scallops

http://seattle.citysearch.com/feature/10243

http://www.meddybemps.com/shells/2draw_scallop.html

BIVALVES•2 SHELLS•FILTER FEEDERS •Only mollusks WITHOUT A

RADULA•Only mollusks WITHOUT

CEPHALIZATION•OPEN CIRCULATION• INDIRECT DEVELOPMENT with

a TROCHOPHORE LARVA•SESSILE as ADULTS

CLASSES of MOLLUSKS

Snails, slugs, conchs, nudibranchshttp://www.seaotter.com/marine/research/tritonia/diomedea/pics/pink_nudibranch.jpg

http://ippc2.orst.edu/potato/grayslugs.jpg

http://mysticearth.us/images/conch.JPG

GASTROPODS•MOST HAVE 1 SHELL•MOST SLOW CRAWLING

– VEGGIE GRAZERS with RADULA •CEPHALIZATION•OPEN CIRCULATION•Aquatic ones have INDIRECT

DEVELOPMENT with a TROCHOPHORE LARVA

•TORSION (twisting of body)

http://www.geocities.com/TheTropics/2428/directory.html

CLASSES of MOLLUSKS

CEPHALOPODS

http://www.seasite.niu.edu/indonesian/Themes/Animals/sea/images/cuttlefish.jpg

CEPHALOPODS• MOST HAVE NO SHELL• FAST SWIMMING CARNIVORES (RADULA)• CEPHALIZATION• Only mollusks with CLOSED CIRCULATION• Only group with DIRECT DEVELOPMENT• CHROMATOPHORES for camouflage• MOST INTELLIGENT of the

INVERTEBRATES• Many have INK for defense