Plants respond to threats (IMAGE) Heinrich-Heine University Duesseldorf Caption (A) Silver electrodes placed on the surface of leaf petioles of the plant Arabidopsis thaliana (Thale cress) allow measurements of wounding-induced electrical signals. (B) Enlarged section of two leaves producing a genetically encoded fluorescent biosensor indicating cellular calcium levels (in pseudo-colors). The bright coloration indicates an increase in calcium levels, which was triggered by wounding of the right leaf and has spread to the left leaf. Placement of the silver electrodes on the surface of the petioles (arrows) allows simultaneous detection of the electrical activity of the plant. Credit F. Atanjaoui & T. Kleist Usage Restrictions Picture can only be published when permitted by F. Atanjaoui and T. Kleist 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.