Arabidopsis Root Tip (image) Norwich BioScience Institutes Caption This is a confocal laser scanning micrograph of an Arabidopsis root tip in which the cell outlines are marked in green by a fluorescent protein. The orange region marks stem cells that died after treatment with a drug that damages DNA. Credit John Innes Centre Usage Restrictions None 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.