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itute, , Insu, , of, , GENOME, , EanBan, , Avi, , Avisek Patra, M.Sc, , ura, , Genome, , Symmetry, Division of body into equal parts, by lines and, are four types..., , planes is called symmetry. Theoretically there, , Asymmetry:, plane,, , An animal can't be divided into similar halves, by section passing through any, these animals are highly irregular in shape. This, type of symmetry is called'asymmtry., , e.g: Amoeba, , Radial symmetry:, Certain animals have a symmetrical body. It have an axis alongits body, öne end of their axis, that bears mouth is called the oral end and the opposite end is called aboral end. All plane, , passing through the center are called radial planes If the body cut älong any radial plane along, the body axis (longitudinal axis) and if results into two similar halves then the symmetry is called, radial symnmetry. e.g: echinoderms &, , most cnidarians., , Bi radial symmetry is variation ofradial symmetry, in this type synmetry there is, , only two planes of symmetry, one through the longitidinal and median longitudinal (sagittal, axis) and other to thelongitudinalánd tight angleto the sagittal axis and makes two equal halves., , eg Ctenophora(Pleurobraclya), Bi lateralsymmetry:Bilateralsymmetry implies that the median longitudinal or sagital, plane passing through the animalsbody divides it into 2 extermally identical halves which are, , rough mirorimage ofeach other., , Bilateral sy, , etry is characteristic of most successful & higher animals. First phylum of animal, kingdomto exhibit bilateral symmetry is Platyhelminthes., , Spherical symmetry: This type of symmetry is found in animals whose body is in the, form of a sphere. Its have a central point and all plane passing through the center cut body into, , two equal halves. This type of symmetry is found in floating forms of animals. e.g. Vobax,, Actinophrys, , Radial, , Biradial, , Sphere