التعريف: overall repetitive or reflective pattern in the body of one individual of this taxon. eg: bilateral symmetry, rotational symmetry, radial symmetry
التعريف: A plain without trees (apart from those near rivers and lakes); it is similar to a prairie, although a prairie is generally considered as being dominated by tall grasses, while short grasses are said to be normal in the steppe. It may be semi-desert, or covered with grass or shrubs or both, depending on the season and latitude.
التعريف: A distinct juvenile stage many animals undergo before metamorphosis into adults. Animals with indirect development such as insects, amphibians, or cnidarians typically have a larval phase of their life cycle. [ http://en.wikipedia.org/wiki/Larva ]
التعريف: superposition compound eyes where each ommatidium is equipped with a lens cylinder arrangement, producing the equivalent of a pair of lenses, with the first lens producing a small image halfway down the structure and the second lens turning the image back into a parallel beam. In the process the ray direction is reversed. Thus, the emerging beam is on the same side of the axis as the entering beam—the condition for obtaining a superposition image from the whole array.
