Phylum Echinodermata

tube feet

arise out the ambulacral grooves on the oral side of the sea star. allows for locomotion, attachment, and grabbing

aboral

the surface opposite the mouth

water vascular system

a network of water-filled canals that relies on water pressure to operate the sea star’s tube feet

ossicles

these calcium carbonate plates compose the endoskeleton of the sea star

coelomic

the fluid that bathes the sea star’s internal organs and transports nutrients to all parts of its body (because sea stars have no blood).

evisceration

sea cucumbers expel their sticky and toxic guts through their anus to defend themselves

echinoderm

spiny skinned animals

radial

part of the water vascular system that arises from the ring canal and extends down each arm

ampullae

each of the muscular bulb-like sacs that squeeze water into the tube feet

pedicellaria

minute pincer-like organs on the aboral surface of sea stars that help keep the body surface clean and capture tiny food particles

pentamerous

symmetry based on five parts

ring

the canal that encircles the inside of the central disk and is part of the water vascular system

madreporite

a porous plate that allows water into the water vascular system of the sea star

fission

sea stars can asexually reproduce, if necessary, by separating their central disk into two pieces and regenerating the new parts

bilateral

type of symmetry only shown by the larval form of an echinoderm before it metamorphosizes into adult form

ambulacral grooves

each of the channels on the oral surface of a sea star through which tube feet protrude

aristotle’s lantern

the set of jaws and associated muscles used by sea urchins to bite off food

spawning, external

sea stars can sexually reproduce by _____, and fertilization is _________.

brittle star

having long, slender, flexible arms and a distinct central disc

sea urchin

long, moveable spines and round, rigid endoskeleton

sand dollar

a sea urchin that is flat instead and contain tube feet on the oral side

sea urchin

class echinoidea

brittle star

class ophiuroidea

sea cucumber

class holothuroidea

“true stars”

class asteroidea

sea lilies (and feather stars)

class crinoidea

connects the madreporite to the ring canal

stone canal

canal that extends down each arm

radial

symmetry of larval form of sea star

bilateral

pyloric caeca

digestive gland