This false-color image shows a cell from the epidermis of an Arabidopsis thaliana plant; the cell has been marked with fluorescent imaging sensors designed to detect the sugar glucose. In this image, only the densely packed interior of the cell in which most metabolic functions occur—called the cytosol—is targeted by the glucose sensors. The dark area sits inside the vacuole—a large storage organelle that can occupy up to 90% of the cell’s volume. (Image courtesy Sylvie Lalonde and Wolf Frommer; click for higher resolution.) Back to release