Echinoderms Flashcards
A marine invertebrate
Echinoderm
A skeleton located on the inside of the body
Endoskeleton
A defensive organ like a minute pincer present in large numbers on an echinoderm.
Pedicellariae
A perforated plate by which the entry of seawater into the vascular system of an echinoderm is controlled.
Madreporite
One of the numerous minute canals lined with choanocytes which radiate from the paragastric cavity in some sponges and end just below the surface of the sponge.
Radial Canal
The circular water tube that surrounds the esophagus of echinoderms.
Ring Canal
An appendage the echinoderm uses to move things or itself.
Arm/Ray
Symmetry on all angles of an organism, such as a jellyfish.
Radial Symmetry
Symmetry on both sides of the organism, such as a human
Bilateral Symmetry
A network of water vessels in the body, the tube feet being operated by hydraulic pressure within the vessels.
Water Vascular System
Extends from the mouth to the end of each ray or arm.
Ambulacral Groove
A very small bone, especially one of those in the middle ear.
Ossicles
One of the tubular pouches opening into the alimentary canal in the pyloric region of most fish.
Pyloric Caecum
The distal aperture of the stomach, opening into the duodenum.
Pyloric Stomach
The large anterior foregut occupies much of the posterior aspect of the head and the anterior thoracic body cavity.
Cardiac Stomach
