radial symmetry
[L. radius, a spoke of a wheel + Gk. summetros, symmetry]
Characterizing a body shaped like a pie or barrel, with many equal parts radiating outward like the spokes of a wheel; present in cnidarians and echinoderms.
radiation ...
radial symmetry. HOWEVER, their larvae have bilateral symmetry so the echinoderms probably evolved from bilaterally symmetrical ancestors and properly belong in the Bilateria.
water vascular system.
radial symmetry
Characterizing a body shaped like a pie or barrel, with many equal parts radiating outward like the spokes of a wheel; present in cnidarians and echinoderms.
radial symmetry. A morphological condition in which the parts of an animal are arranged concentrically around an oral-aboral axis, and more than one imaginary plane through this axis yields halves that are mirror images of each other.
The phylum Cnidaria contains 10,000 species characterized by adult bodies having radial symmetry. Cnidarians are aquatic, mostly all marine. The cnidarian body has only the ectoderm and endoderm tissue layers, making this group diploblastic.
Most adults have radial symmetry, while their larvae are bilaterally symmetrical. Echinoderms have an endoskeleton consisting of calcareous plates bearing spines.
They have radial symmetry and they have two layers of cells with a rudimentary middle layer. They have one of two basic body plans both of which are radially symmetrical, the medusa and polyp (an upside down medusa).
bilateral symmetry, or two-sidedness, in vertebrates, etc, is that in which the body can be divided into symmetrical halves by a vertical plane passing through the middle; radial symmetry, as in echinoderms, ...
Radiata - group of simple animals with radial symmetry, including the cnidarians (or coelenterates) and ctenophores.
Coelomata (Cnidaria): A phylum in the Animal Kingdom. They are invertebrate aquatic animals showing radial or biradial symmetry. Examples are corals, sea anemones, jelly fish. See also Cnidaria in the Shape of Life (PBS).
 See also: Organ, Animal, Plant, Trans, Origin
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