DICTIONARY

DICTIONARY VERTEBRATE: A vertebrate is an animal that has a backbone and a skeleton. INVERTEBRATE: An invertebrate is an animal without a backbone. MAMMAL: Any vertebrate of the class Mammalia, having the body more or lesscovered with hair, nourishing the young with milk from the mammaryglands, and, with the exception of the egg-laying monotremes, giving birth to live young. BIRD: Any warm-blooded vertebrate of the class Aves, having a body covered with feathers, forelimbs modified into wings, scaly legs, a beak, and no teeth and bearing young in a hard-shelled egg. FISH: Any of various cold-blooded, aquatic vertebrates, having gills, commonly fins, and typically an elongated body covered with scales. REPTILE: Any cold- blooded vertebrate of the class Reptilia, comprising the turtles, snakes, lizards, crocodilians, amphisbaenians, tuatara, and various extinct members including the dinosaurs. AMPHIBIAN: Any cold-blooded vertebrate of the class Amphibia, comprising frogsand toads, newts and salamanders, and, caecilians, the larvae being typically aquatic, breathing by gills, and the adults beintypically semiterrestrial, breathing by lungs and through the moist glandular skin. ARTHROPOD: Any invertebrate of the phylum Arthropoda, having a segmented body,jointed limbs, and usually a chitinous shell that undergoes moltings,including the insects, spiders and other arachnids, crustaceans, andmyriapods. ECHINODERM: Any marine animal of the invertebrate phylum Echinodermata, having aradiating arrangement of parts and a body wall stiffened by calcareouspieces that may protrude as spines and including the starfishes, seaurchins, sea cucumbers, etc. ANNELID: Any segmented worm of the phylum Annelida, including theearthworms, leeches, and various marine forms. MOLLUSK: Any invertebrate of the phylum Mollusca, typically having a calcareousshell of one, two, or more pieces that wholly or partly enclose the soft,unsegmented body, including the chitons, snails, bivalves, squids, andoctopuses. CRUSTACEAN: Any chiefly aquatic arthropod of the class Crustacea, typically havingthe body covered with a hard shell orcrust, including the lobsters,shrimps, crabs, barnacles, and wood lice. Tomado de: http://dictionary.reference.com/