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innate behavior an inherited behavior that does not depend on the environment or experience
learned behavior a behavior that has been learned from experience
invertebrates an animal that does not have a backbone
ganglion a mass of nerve cells
coelom a body cavity that contains the internal organs
open circulatory system a circulatory system in which the circulatory fluid is not contained entirely within vessels; a heart pumps fluid through vessels that empty into spaces called sinuses
closed circulatory system a circulatory system in which the heart circulates blood through a network of vessels that form a closed loop; the blood does not leave the blood vessels, and materials diffuse across the walls of the vessels
segment any part of a larger structure, such as the body of an organism, that is set off by natural or arbitrary boundaries
exoskeleton a hard, external, supporting structure
compound eye an eye composed of many light detectors
antenna a feeler that is on the head of an invertebrate, such as a crustacean or an insect, and that senses touch, taste, or smell
metamorphosis a phase in the life cycle of many animals during which a rapid change from the immature form of an organism to the adult form takes place
endoskeleton an internal skeleton made of bone and cartilage
water vascular system a system of canals filled with a watery fluid that circulates throughout the body of an echinoderm
gut the digestive tract
Created by: tlindstrom