3. What are the basic
morphological features of
echinoderms?

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Echinoderms, as the indicates
(echino = , derma = skin),
creatures with spines from an
endoskeleton. endoskeleton is
made calcareous plaques that
spines contain pedicellaria, pincers
used to the body and help the
capturing prey. They also a
hydrovascular system as the
ambulacral . Adult echinoderms
have symmetry; the radial
in these animals
secondary, present only adults.