At some point after the different germ layers are defined, organogenesis begins. The first stage in vertebrates is called neurulation, where the neural plate folds forming the neural tube.
Other common organs or structures which arise at this time include the heart and somites, but from now on embryogenesis follows no common pattern among the different taxa of the animal kingdom.
In most animals organogenesis along with morphogenesis will result in a larva.
The hatching of the larva, which must then undergo metamorphosis, marks the end of embryonic development.
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