Human sperm cell (IMAGE) University of Münster Caption Beating pattern of a human sperm cell before (left) und after (right) activation of CatSper. The more powerful beat is required to fertilize the egg Credit University of Münster / Strünker group Usage Restrictions Only use in context with this press release 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.