characteristics of arthopoda,mollusca,echinodermata,protochordata,

The characteristics of Molluscans are:

i)Body is soft and bilaterally symmetrical.

ii) Body is divided into anterior head, ventral muscular foot and dorsal visceral mass. Foot is used for moving around.

iii) The coelomic cavity is reduced.

iv) Body shows little segmentation.

v) They have an open type of circulatory system.

vi) They possess kidney-like organs for excretion.

vii) Respiration occurs by gills, mantle or lung.

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