blastoderm: the germinal membrane from which the organs of the embryo are formed. Explanation of Terms Used in Entomology John. B. Smith He it was who introduced the terms Keimhaut (blastoderm) and Keimblatt (germ-layer).
Child Study. Child study, also called paidology or experimental pedagogy, was the attempt to apply the methods of modern science to the investigation of children in order to discover the laws of normal child development.
retrospective study, a study in which a search is made for a relationship between one phenomenon or condition and another that occurred in the past (e.g., the exposure to toxic agents and the rate of occurrence of disease in the exposed group compared with a control group not exposed). study. a scholarly examination.