{description}Try pressing a flashlight against your fingertip, and you’ll f nd that it produces an eerily pink glow reminiscent of E.T.’s glowing fingers. This phenomenon occurs because light can penetrate a small distance through living tissues. Transillumination is used in two-photon microscopy to create nanoscale images of living tissues. Stanford scientists have been using and perfecting this method of imaging live cells to gain a better understanding of cellular function in our bodies. {/description}