Echinoderms lack a centralized nervous system.
Echinoderms include starfish, sea urchins, and sea cucumbers.
Starfish, sea urchins and sea cucumbers lack a centralized nervous system.
Starfish, sea urchins and sea cucumbers lack a what?

a. characteristics
b. the body's largest organ
c. watery habitat
d. centralized nervous system
e. functioning arm
f. underwater life
g. biological diversity
h. epidermis and dermis