This image shows a water droplet suspended in an emulsion of olive oil (black and purple) and lipids, molecules that serve as the building blocks of cell membranes. Each lipid has been labeled with a red fluorescent marker, and what looks like red and yellow flames are the markers reacting to a beam of UV light. Their glow shows lipids adhering to the surface of the water droplet, which will soon engulf the droplet to form a single lipid bilayer, which can then be transformed into a lipid bilayer that resembles a cell membrane. Scientists use these bubbles, called liposomes, as artificial cells for various research purposes. In this case, it is structural biology studies.