Members of this phylum often use ampulla to move and, like Chordata, are deuterostomes.
One class in this phylum can projectile-vomit its organs and is called Holothuroidea; another class is called Ophiuroidea. Members of this phylum often use ampulla to move and, like Chordata, are deuterostomes. A structure known as stereom [*] often gives members of this phylum a calcified endoskeleton, and the madreporite is connected to their tube feet within the water vascular system. For 10 points, name this animal phylum generally expressing pentaradial symmetry, which includes sea stars and sea urchins and is named for their spiny skin.
One class in this phylum can projectile-vomit its organs and is called Holothuroidea; another class is called Ophiuroidea.
{Echinodermata} or {echinoderms}