التعريف: overall repetitive or reflective pattern in the body of one individual of this taxon. eg: bilateral symmetry, rotational symmetry, radial symmetry
التعريف: An interaction relationship between two organisms living together in more or less intimate association in a relationship in which both organisms benefit from each other
التعريف: The largest scale biogeographic division of the earth's surface based on the historic and evolutionary distribution patterns of plants and animals.