Deoxyribonucleic acid (DNA) is a chemical that was first isolated in the 1860s, although its significance in terms of genetics was not realized until the mid-twentieth century. The nucleic acid is found predominantly in the nuclei of eukaryotic cells, but certain other organelles, such as mitochondria and chloroplasts, also contain DNA. In prokaryotes, the nucleic acid is located throughout the entire cell. Oswald Theodore Avery was the first scientist to produce convincing evidence that DNA was responsible for the transmission of genetic information, but James Watson and Francis Crick were central to the discovery of how the nucleic acid carries out this function. Their determination that DNA exists as a double helix was a key step on the way to the modern understanding of genetic transmission.

The EOMA cell culture featured in the digital image above was labeled with MitoTracker Red CMXRos, Alexa Fluor 488 conjugated to phalloidin, and DAPI, targeting the intracellular mitochondrial network, cytoskeletal F-actin, and nuclear DNA, respectively. Images were recorded in grayscale with a QImaging Retiga Fast-EXi camera system coupled to an Olympus BX-51 microscope equipped with bandpass emission fluorescence filter optical blocks provided by Omega Optical. During the processing stage, individual image channels were pseudocolored with RGB values corresponding to each of the fluorophore emission spectral profiles.