Some do but not all.
The radula (or some form of the radula) is found in all classes of mollusks except bivalves (organisms with two shells such as clams).
No. Oysters do not have a radula
Echinoderms live only in the sea.
No not all Echinoderms have backbones like the starfish
Yes Eventually echinoderms do live in water.
Bivalves do not have a radula.
Yes, all echinoderms have radial symmetry.
no, a lobster is a crustacean, not an echinoderm
A mantel, a radula and a muscular foot.
No it is not.
echinoderms
Yes they do