JiB 116 Vc310Mollusca, Annelida

8/16/2019 JiB 116 Vc310Mollusca, Annelida

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Phylum Mollusca

2nd

largest phylum after ArthropodaLatin molluscus means soft

90 000 living sp

70 000 fossil sp

Very diverse group incl: chitons, snails,

slug, clams, mussels, oysters, suids,

octopus!


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" #a$itats range from tropics to polar seas

" %an $e found up to 7000 m asl" &n seas, deep seas, ponds, la'es, rivers,

mudflats, terrestrial

" (conomic importance eg food, pearl, shellfor trin'ets

" Pests eg Toredo )ship*orms+ garden andvegeta$le pests

" ome are parasites, some medicinal use


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" %haracteristics of Phylum Mollusca

" -ody *ith mantle, mantle cavity, gills ,lungs and foot

" Marine, f*ater or terrestrial ha$itats

" .riplo$lastic $ody and $ilateral symmetry" %oelom limited to around heart

" %omple/ digestive system )radula, ciliary+

" ound, diagonal and longitud muscles" 1ervous system


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" ensory organs eg touch, smell, taste,vision, euili$rium

" e/ual reproduction

" #as one or t*o 'idneys

" -reathing thru lungs, gills, mantle or $odysurface

" pen circulatory system )$lood not

enclosed in vessels+


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" %lassification

" %lasses 3 %audofoveata

3 olenogastres

3 Polyplacophora 3 Monoplacophora )see diagram at 4ig 56!2+

3 astropoda )Pg 888+

3 %ephalopoda

3 -ivalvia

3 caphopoda


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" Phylum Annelida

" )annelus, latin little ring+, segmented*orms

" 5 000 sp

" (arth*orms and f*ater *orms )%l!ligochaeta+

" Leeches )%l! #irudinida+

" Marine *orms )%l! Polychaeta+


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" eneral features:

3 egments )metamerism+ 3 etae

3 Prostomium, peristomium, segmented

$ody and ends in pygidium 3 #ydrostatic s'eleton

3 %litellum

3 Peritonium )epithelium lining $ody *all+ 3 mesentries


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Documents

JiB 116 Vc310Mollusca, Annelida