Video of Sperm (VIDEO) Optica This video is under embargo. Please login to access this video. To view this video please enable JavaScript, and consider upgrading to a web browser that supports HTML5 video Caption This video shows the track of a single sperm cell with a bent tail, in two dimensions (left) and three dimensions (right). Credit Credit: <i>Biomedical Optics Express</i>. Usage Restrictions Must include caption and credit. 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.