Thale cress flower. Fluorescence micrograph of a flower from a thale cress (Arabidopsis thaliana) plant, showing the reproductive structures. Pollen grains (dark dots) can be seen in the anthers (round) on the end of the stamens (male parts), which are either side of the carpel (female parts, centre, vertical, yellow). Here both male and female parts have matured at the same time meaning that self-fertilisation has taken place. A fluorescence microscope is an optical microscope that uses fluorescence and phosphorescence instead of, or in addition to, reflection and absorption - as used by normal light microscopes.