title: Experimental studies on axial polarity in hydra.
mesh_terms: D000818:Animals; D001693:Biological Transport, Active; D003063:Cnidaria / Q000254:growth & development*; D004058:Diffusion; D008954:Models, Biological; D009024:Morphogenesis; D012038:Regeneration; D014184:Transplantation, Homologous