Question

four molluscs and two echinoderms ​

Answer 1

Answer:

(1) Molluscs are multicellular organisms

(2) They have a bilateral symmetry, but snails are asymmetrical

(3) They are triploblastic animals.

(4) They are coelomate animals.

(5) They have organ system grade of organization.

(6) The body is soft and non-segmented.

(7) The soft body is covered by a fleshy fold of the body wall. It is called mantle.

(8) The molluscs are provided with one or two calcareous shells.

(9) Respiration is carried out by the gills or pulmonary chambers.

(10) The digestive system is well developed.

(11) The circulatory system is of an open type.

(12) The excretory organ is the kidney.

(13) The nervous system is well developed.

(14) The sensory organs are eyes, statocysts and osphradia.

(15) Sexes are separate in them, or they are hermaphrodites.

(16) The development in their case in either direct or indirect

Explanation:

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