About the Mollusca The phylum Mollusca contains some of the most familiar invertebrates, including snails, slugs, clams, mussels, and octopuses
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Characteristics1)Bilaterally symmetrical.
2)Body has more than two cell layers, tissues and organs. 3)Body without cavity. 4)Body possesses a through gut with mouth and anus. 5)Body monomeric and highly variable in form, may possess a dorsal or lateral shells of protein and calcareous spicules. 6)Has a nervous system with a circum-oesophagal ring, ganglia and paired nerve chords. 7)Has an open circulatory system with a heart and an aorta. 8)Has gaseous exchange organs called ctenidial gills. 9)Has a pair of kidneys. 10)Reproduction normally sexual and gonochoristic. 11)Feed a wide range of material. 12)Live in most enviroments. |