Day 4 embryoid (IMAGE) University of Cambridge Caption Day 4 embryoid showing an inner epiblast like domain in magenta that has apico-basal polarity (yellow apical, blue basal), similar to the epiblast of the human embryo just after implantation. Credit University of Cambridge Usage Restrictions In relation to this research only. License Original 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.