Cyan PSII on Leaf (IMAGE) St. John's College, University of Cambridge Caption Competing electron transfer pathways are found within Photosystem II using an advanced technique known as protein-film photoelectrochemistry. In one pathway, electrons are extracted from water by the enzyme. In the other, electrons are hijacked, generating reactive radical species. Credit Jenny Zhang 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.