• Using confocal microscopy, scientists can study both living and preserved samples. One application for which confocal microscopy has been particularly useful is evaluating the effects of chemicals produced by marine organisms on specific structures or processes in cancer cells. This has helped scientists determine the mechanism by which these chemicals kill cancer cells, and could lead to the development of new drugs to treat cancer. Another application of this technology is the identification of unique microorganisms that live in marine invertebrates such as sponges.