Ch 38 – Echinoderms and Invertebrate Chordates Vocabulary Review Ch 38 – Echinoderms and Invertebrate Chordates

A radially symmetrical marine invertebrate that has an endoskeleton, such as a starfish, a sea urchin, or a sea cucumber Echinoderm

One of the small, calcium carbonate plates that make up the endoskeleton of an echinoderm Ossicle

Water-vascular system A system of canals filled with a watery fluid that circulates throughout the body of an echinoderm Water-vascular system

One of many small, flexible, fluid-filled tubes that project from the body of an echinoderm and that are used in locomotion, feeding, gas exchange, and excretion Tube foot

In some protists and invertebrates, a protective covering that the organism secretes or builds around itself Test

On the surface of some echinoderms, very small pincers that are used for protection against ectoparasites Pedicellaria

The porous structure through which water enters and exits the water-vascular system of echinoderms Madreporite

A tube that connects the madreporite to the ring canal Stone canal

Canal that encircles the mouth of an echinoderm Ring canal

Canals that extend from the ring canal down each of the rays of the starfish, delivering water to ampullae and tube feet Radial canal

On the upper end of a tube foot of an echinoderm, a bulblike sac that forces water into the tube foot and causes the tube foot to expand Ampulla

Stomach of the sea star that can turn inside out through its mouth; transfers food to the pyloric stomach Cardiac stomach

Stomach that connects to a pair of digestive glands in each arm Pyloric stomach

Bilaterally symmetrical, free-swimming larva of a sea star Bipinnaria

An opening from the atrial cavity to the exterior in certain fish Atriopore