echinoderm Flashcards
Endoskeleton
the internal bone or cartilage structure of animals.
Pedicellariae
small, stalk-shaped structure of the sea urchin and other echinoderms.
Madreporite
essential part of the circulation system in echinoderms.
Radial canal
a tube extending outward along each ambulacral area from the circumoral canal in most echinoderms
Arm / Ray
the bony or cartilaginous spines of the fin of a fish
Radial Symmetry
arrangement of parts of an organism around a single main axis.
Bilateral Symmetry
the balanced distribution of duplicate body parts or shapes within the body of an organism.
Water Vascular System
is a hydraulic system used by echinoderms.
Ambulacral Groove
extends from the mouth to the end of each ray or arm.
Ossicles
A small bone, particularly applied to the tiny bones of the middle ear.
Pyloric Caecum
tubular pouches opening into the alimentary canal
Pyloric Stomach
The passage at the lower end of the stomach that opens into the duodenum.
Cardiac Stomach
occupies much of the posterior aspect of the head and the anterior thoracic body cavity.
Ampullae
enlargement of the ducts from the liver and pancreas
Gonad
The sex organ producing gametes.
Central Disc
Central region of sea stars & brittle stars from which rays or arms radiate; contains madreporite, mouth, & anus
Tube Feet
fluid-filled muscular tubes of echinoderms.
External Fertilization
is a male organism’s sperm fertilizing a female organism’s egg outside of the female’s body. I
Regeneration
the process of renewal, restoration, and growth that makes genomes, cells, organisms, and ecosystems
Sea star
star-shaped and usually has five rays, though the number of rays varies from five to forty or more
Brittle star
They crawl across the sea floor using their flexible arms for locomotion
Sea urchin
are usually enclosed in thin brittle globular tests covered with movable spines.
Sand dollar
refers to species of extremely flattened, burrowing sea urchins
Sea lilies
marine animals that make up the class Crinoidea of the echinoderms
Feather stars
occur chiefly on rocky bottoms in shallow water.
Sea cucumbers
are marine animals with a leathery skin and an elongated body containing a single, branched gonad
Sea daisies
has a delicately plated dorsal surface which delimits the disc-like body with a single peripheral series of flattish, oar blade-like spines.
