image: A cross-section of a stem and seven small leaves (microphylls) from an Australian Beefwood (Casuarina cunninghamiana). A special Ultraviolet (UV) light was used to reveal the different colors under a microscope. Items under a UV-lamp fluoresce and do not look the same color as under daylight. The red fluorescence is from chlorophyll in the very small pentagon shaped leaves. The blue fluorescence is from secondary metabolites in the vascular (central) and epidermal (outer) tissue. view more
Credit: Courtesy: Arizona State University