bilateral symmetry

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bilateral symmetry A type of arrangement of the parts and organs of an animal in which the body can be divided into two halves that are mirror images of each other along one plane only (usually passing through the midline at right angles to the dorsal and ventral surfaces). Bilaterally symmetrical animals are characterized by a type of movement in which one end of the body always leads. In botany this type of symmetry is usually called zygomorphy when applicable to flowers (e.g. foxglove and antirrhinum flowers are zygomorphic). Compare radial symmetry.

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