X-RAY-MICROANALYSIS OF ATOMS IN DEVELOPING EMBRYOS OF THE RED-SPOTTEDNEWT NOTOPHTHALMUS-VIRIDESCENS

Energy dispersive X-ray microanalysis (EDX) has contributed much to th e understanding of bound atoms and free ions and their functions in ph ysiological processes in a variety of biological systems in adult orga nisms. The current investigation details the in situ tissue and cellul ar distribution of the 'physiologically relevant' elements: Na, Mg, I? S, Cl, K, and Ca during embryogenesis from the fertilized egg through to the tailbud stage of the red-spotted newt Nolophthalmus viridescen s. Results demonstrate for the first time that morphologically distinc t regions of newt embryos possess characteristic elemental profiles. I n all probability, such elemental signatures are implicated in the dev elopment, structural architecture, and functional dynamics of various tissues as newt embryogenesis ensues.