The primary purpose of Space Station life-sciences research will be to further our understanding of fundamental biological processes by exploiting the microgravity environment of space. In addition, life-sciences studies will ensure the health and well-being of the astronauts and other crewmembers on missions that can last for months or even years. Animals will be used in studies of, for example, bone mineral loss, muscle changes, cardiovascular alterations, fluid and electrolyte shifts, abnormal vestibular function, behavior patterns, and immune response. It is reasonable to assume that Space Station life-sciences research will also have important terrestrial applications. Life scientists aboard the Space Station will work in one of the four habitable modules that will constitute the initial Space Station configuration. Typical nonhuman life-sciences equipment will include animal holding facilities, plant-growth chambers, work stations, video camera and recording systems, data analysis systems, refrigerators, freezers, and storage systems.