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26-1 Quiz


invertebrate animal that does not have a backbone or vertebral column
vertebrate animal that has a vertebral column, or backbone
feedback inhibition process in which the product or result stops or limits the process
parasite organism that lives within or on another organism and harms that organism by feeding on it
blastula hollow ball of cells formed when a zygote undergoes a series of divisions
protosome animal whose mouth is formed from its blastopore
deuterosome animal whose anus is formed from the blastopore of a blastula
anus opening through which wastes leave the digestive tract
endoderm innermost germ layer of most animals; develops into the linings of the digestive tract and much of the respiratory system
mesoderm middle germ layer of most animals; gives rise to muscles and much of the circulatory, reproductive, and excretory systems
ectoderm outermost germ layer of most animals; gives rise to outer layer of the skin, sense organs, and nerves
radial symmetry body plan in which body parts repeat around the center of the body; characteristic of sea anemones and sea stars
bilateral symmetry body plan in which only a single, imaginary line can divide the body into two equal halves; characteristic of worms, arthropods, and chordates
cephalization concentration of sense organs and nerve cells at the front of an animal's body
Created by: 100critter