How a tadpole becomes a frog.
D000818:Animals; D001001:Anura / Q000502:physiology*; D005246:Feedback; D007030:Hypothalamo-Hypophyseal System / Q000502:physiology*; D066298:In Vitro Techniques; D008675:Metamorphosis, Biological; D013961:Thyroid Gland / Q000502:physiology*