Lesson 21 Terms Flashcards
Ampulla
Muscle structures on the internal side of tube feet
Anthozoa
sea anemones and corals
Class Asteroidea
sea stars
Class Echinoidea
sea urchins and sand dollars
Class Holothuroidea
sea cucumbers
Class Ophiuroidea
brittle stars
Cnidocytes
stinging cells on tentacles
Contractile cells
bend the organism’s body allowing it to move through the water
Coral
colonial creatures: each coral is an individual multicellular organism, but they form a colony that’s interdependent on one another
Epithelium
contains nerve cells and contractile cells
Endoskeleton
an internal skeleton made up of plates called ossicles
Class Hydrozoa
hydra, hydroid colonies, and the Portuguese Man-of-War
Lateral canals
branch perpendicularly off the radial canals and terminate at tube feet
Medusa
a) umbrella shaped body with its mouth facing downward and tentacles extending around it
b) Motile
Mesoglea
A jelly-like substance between the inner layer and outer layer of cells in a cnidarian
Nematocysts
coiled tubes containing an attached barb that discharges a toxin when launched
Ossicles
plates that make up the endoskeleton
Papulae
tubular extensions that assist in gas exchange
Pentaradial symmetry
have 5 arms evenly distributed around a central disc
Phylum Echinodermata
sea stars and sea urchins
a) cup-shaped tubular body form with a mouth and tentacles at one end, and a base that attaches to a hard surface on the other end
b) Sessile
Polyp
Radial canals
extend from central part of the echinoderm’s body down each ray
Ring canal
where water enters, surrounding the mouth
Class Scyphozoa
jellyfish
Sieve plate
filters sea water before it enters the system
Symbiotic
relationships with certain organisms where both organisms benefit from one another
Symbiotic
relationships with certain organisms where both organisms benefit from one another
Tube feet
hollow feet-like knobs
Water vascular system
a system of tubes filled with water extending through their entire body
