Understanding How Plants Conserve Water (IMAGE) University of Maryland Caption Infrared thermal images of two canola plant (Brassica napus) leaves show differences in leaf surface temperature caused by variations in the size of the plant's microscopic pores (stomata) formed by a pair of guard cells. These pores allow plants to "breathe" by controlling water loss and carbon dioxide intake for photosynthesis. Credit June Kwak, University of Maryland 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.