phylum Mollusca

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  1.                                             PHYLUM -   MOLLUSCA                                                                     characters-                                                                                                                                 1)unsegmented                                                                                                                                2)presence of shell mantle,visceral mass and foot.                                                                      3)circulatory system open.                                                                                                             4)excretion by paired metanephridia. 
                                                                                                                                                                                                                                                      EXAMPLE- PILA, UNIO, OCTOPUS,DORIS etc.                 

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