title: The role of zimogen cells in hydra exposed to ultraviolet light (2535 A).
mesh_terms: D000818:Animals; D004064:Digestive System / Q000166:cytology* / Q000528:radiation effects; D004475:Ectoderm / Q000166:cytology* / Q000528:radiation effects*; D006829:Hydra / Q000528:radiation effects*; D011830:Radiation Effects; D013997:Time Factors; D014466:Ultraviolet Rays