Model of the Human Cilium Frame (IMAGE) Université de Genève Caption This is a model of the human cilium frame (left), whose cross-section shows the nine microtubule doublets (bottom right); the dotted frame surrounds a doublet. Top right: atomic model of a doublet formed in vitro. Credit © UNIGE 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.