Adi Beal, Lynsey Brinker,
Deanna Holby, Rylie Williams
Symmetry in mollusks
 Bilateral symmetry
How do mollusks move?
 Most – muscular foot
 Tentacles
 Shells
http://gotmuscle.weebly.com/mollusca.html
Nervous system
 Present nervous system
 Nerve bundles
 Ganglia
 Squid-large developed eyes similar to human
Digestive System
 Siphon system
 Waste
Excretory system
 Nephridium
 Kidney
 One-way
Circulatory system
 Cephalopods-closed
 Gastropods and Bivalves-open
Respiratory System
 Siphons
 Gills
Support of skeletal system
 Outer shell
 Soft body
 Muscular foot
 Tentacle's
Reproductive system
 Sexually
 Gonad
Three main classes
 Gastropod/Univalves
 Bivalves
 Cephalopods
http://www.isgs.uiuc.edu/outreach/geology- http://www.thecanadianencyclopedia.ca/en/
resources/gastropods
article/mollusc/
http://w3.shorecrest.org/~Lisa_Peck/MarineBi
o/syllabus/ch7invertebrates/Invertwp/inv_class
_of_06_wp/jiali_cuttlefish/classification.htm
Gastropods/Univalves
 Largest group of mollusks’
 Snails, conchs (univalves), abalones, whelks, sea slugs, and garden slugs
 On shell (except slugs)
 rhythmic contraction of muscular foot
 Use radula to scrape up food
islandcolors.com
www.slugwatch.co.uk
www.caribbeanfmc.com
Bivalves
 Clams, oysters, and scallops
 Two-part, hinged shell joined by strong muscles
 Close shell by contracting muscles
 Well adapted to living under water
 Clams move with their foot
 Scallops open and close shell rapidly
trueoyster.com
tbep.org
Cephalopods
 Most specialized and complex group
 Squid, octopuses, cuttlefish, and chambered nautiluses
 Foot divided into many tentacles
 All live in water
 Well developed nervous system
 Only mollusks with closed circulatory system
www.arkive.org
www.practicalfishkeeping.co.uk
Why are cephalopods mollusks?
 Similar internal structures
 U shaped digestive track
 mantle
 Used to have a shell
 Now kind of internal
userwww.sfsu.edu
Videos
 Cuttlefish Video
 http://video.nationalgeographic.com/video/worlds-deadliest-ngs/deadliestcuttlefish-hypnosis
 Giant Squid Video
 http://www.discovery.com/tv-shows/curiosity/videos/first-video-of-a-giantsquid.htm
 Scallop Video
 http://www.youtube.com/watch?v=zaYNFQd_7HE
Mollusks are referred to as “soft-bodied”
because…
 Composed of shell and fleshy body
 The shell protects the soft body
 Fleshy part divided into foot & visceral mass
 Organs stored soft, fleshy visceral mass
The real meaning
 Gastropod: “stomach foot”
 Cephalopod: “head foot”
How pearls are created
 In oysters, clams, and mussels
 Foreign substance in shell and mantle
 Mantle creates substance to protect itself
 Mantle layers irritant in mantle substance
 Eventually results in a shell
Coelom
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•
•
•
Body cavity in Metazonas
Testinal canal and Body wall
Seperation
Transports nutrients
Snail diagram
Ganglia
Clam diagram
Palps
Gills
Posterior
Abducto
r
Muscle
Mouth
Anterior
Abductor
Muscle
Foot
Mantle-produces shell
Works Cited
 "Coelom." - Definition from Biology-Online.org. N.p., n.d. Web. 02 Oct. 2014.
<http://www.biology-online.org/dictionary/coelom>.
 "Marine Education Society of Australasia." Marine Education Society of Australasia. N.p., n.d.
Web. 02 Oct. 2014. <http://mesa.edu.au/>.
 "Mollusks." - Acadia's Oceanside Meadows Inn. N.p., n.d. Web. 02 Oct. 2014.
<http://www.oceaninn.com/wildlife/mollusks.htm>.
 N.p., n.d. Web. <http%3A%2F%2Fmolluskscience.weebly.com>.
 N.p., n.d. Web. <http%3A%2F%2Fwww.earthlifenetinverts%2Fmollusca.html>.
 N.p., n.d. Web.
<http%3A%2F%2Fwww.tulane.edu%2Fbfleury%2Fdiversity%2Flabguide%2Fmlannel.html>.
Photo Work Cited
 http://shells.tricity.wsu.edu/ArcherdShellCollection/Illustrations/Nervou
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sSystem.html
http://www.livebinders.com/play/play/307257
http://www.madsci.org/posts/archives/1998-05/892237971.Zo.r.html
http://www.studyblue.com/notes/note/n/mollusks-andannelids/deck/6225786
https://www.google.com/imghp?hl=en&tab=wi&ei=MwuVKakLYy9uASb9YIQ&ved=0CAQQqi4oAg