Fluorescently-dyed <i>Xenopus</i> Embryo Cells (IMAGE) University of Pennsylvania Caption Cardiac neural crest cells in one Xenopus embryo were fluorescently dyed, then transplanted to another embryo and allowed to develop normally, enabling researchers to track which cardiac structures they contributed. Credit Jean-Pierre Saint-Jeannet, University of Pennsylvania Usage Restrictions With attribution License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.