One class in this phylum uses a structure known as Aristotle's lantern to eat.
One class in this phylum uses a structure known as Aristotle's lantern to eat. Organisms in this phylum have calcium carbonate ossicles in a stereom structure, and the ampulla and podium make up their characteristic (*) tube feet. Tube feet branch off from radial and ring canals in this phylum's water vascular system, which is used for movement, feeding, and gas exchange. Like the chordates, they are deuterostomes. The sea cucumbers and Asteroidea demonstrate this phylum's characteristic five-way radial symmetry, as do the sea urchins. For 10 points, identify this invertebrate phylum named for its spiny skin.
One class in this phylum uses a structure known as Aristotle's lantern to eat.
{Echinodermata} [accept {echinoderms}]