Zebrafish Heart (IMAGE) Max-Planck-Gesellschaft Caption This is a reconstructed beating heart of a zebrafish embryo. The muscle layer (myocardium) is represented in red and the endothelium (endocardium and vasculature) is represented in cyan. Credit MPI f. Molecular Cell Biology and Genetics/ Huisken Usage Restrictions None 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.