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| | Animal (Site not responding. Last check: 2007-10-25) |
 | | The simplest Metazoa are radially symmetric and diploblastic, that is, they have two germ layers. |
 | | The outer layer (ectoderm) corresponds to the surface of the blastula and the inner layer (endoderm) is formed by cells that migrate into the interior. |
 | | The Cnidaria (jellyfish, anenomes, corals, etc) are the main diploblastic phylum; the Ctenophora (comb jellies) may also belong here. |
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