Open Stomata (IMAGE) University of Würzburg Caption Gas exchange through the stomata: Carbon dioxide is taken in; at the same time a hundred water molecules (H2O) escape for each CO2 molecule that is taken up. Credit Hedrich & Peter Ache / University of Wuerzburg 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.