Modern technology in life and health sciences brings a new understanding to the study of cells and as a result, the National Science Education Standards emphasize understanding of science and technology. This ERIC Digest describes the central role of cell biology (cytology) in understanding these areas and explains conceptual difficulties and instructional approaches to cells and diseases. Information on resources in the ERIC database and a list of Internet resources on cells and their structure, particularly stem cells, is included. (Contains 18 references.) (YDS)