[Complex biological systems as experimental and prenatal toxicology models].

Experimental biomedical sciences have emphasised the use of model systems in the study and understanding of physiological and pathological processes. Developmental biology, genetics and prenatal toxicology, dealing with cellular differentiation, organogenesis and dismorphogenic alterations, have shown that system models, even those far removed from mammals and humans in the zoological scale (e.g. C. elegans, Hydra, Drosophila), can be useful tools for understanding pathogen mechanisms in developmental toxicology. In particular the study of neural tube and its alterations shows how a biologically complex model (such as the laboratory rodent) necessitates, in turn, a series of models to thoroughly analyse and clarify the limits and levels of research.