التعريف: overall repetitive or reflective pattern in the body of one individual of this taxon. eg: bilateral symmetry, rotational symmetry, radial symmetry
التعريف: Living in the fluid medium (water or air) but unable to maintain their position or distribution independently of the movement of the water/air mass (adapted from Lincoln et al., 1998).
التعريف: Gravel is an environmental material which is composed of pieces of rock that are at least two millimeters (2mm) in its largest dimension and no more than 75 millimeters.
التعريف: The marine benthic biome (benthic meaning 'bottom') encompasses the seafloor and includes such areas as shores, littoral or intertidal areas, marine coral reefs, and the deep seabed.
التعريف: Component found in mineralized skeletal tissue, (a specialized form of biogenic tissue in which the extracellular matrix is mineralized, and which functions in mechanical and structural support.)
التعريف: Hard framework, internal or external, which supports and protects softer parts of plant, animal or unicellular organism, and to which muscles usually attach in animals, includes skeletons (derived from Lawrence, 2005).
التعريف: superposition compound eyes where each ommatidium is equipped with a set of plane mirrors, aligned at right angles, forming a square. Rays entering the eye at an oblique angle encounter two surfaces of each mirror box rather than one surface. In this case, the pair of mirrors at right angles acts as a corner reflector. Corner reflectors reflect an incoming ray through 180 degrees, irrespective of the ray’s original direction. This ensures that all parallel rays reach the same focal point and means that the eye as a whole has no single axis, which allows the eye to operate over a wide angle.