title: Local application of retinoic acid to the limb bond mimics the action of the polarizing region.
mesh_terms: D000818:Animals; D002642:Chick Embryo; D009024:Morphogenesis / Q000187:drug effects*; D014212:Tretinoin / Q000494:pharmacology*; D014921:Wings, Animal / Q000196:embryology
chemical_list: D014212:Tretinoin