Biosensor it affects marine organisms, especially plankton (floating microorganisms) and viruses that attack plankton. Plankton form the base of the marine food chains and are believed to affect our planet's temperature and weather by uptake of CO for photosynthesis. Deneb Karentz, a researcher at the Laboratory of Radio-biology and Environmental Health (University of California, San Francisco) has devised a simple method for measuring ultraviolet penetration and intensity. Working in the Antarctic Ocean, she submerged to various depths thin plastic bags containing special strains of "E. coli" that are almost totally unable to repair ultraviolet radiation damage to their DNA. Bacterial death
Marine mammals as food blubber is used to make seal oil, which is marketed as a fish oil supplement. In 2001, two percent of Canada's raw seal oil was processed and sold in Canadian health stores. There has been virtually no market for seal organs since 1998. Archaeological evidence indicates that for thousands of years, indigenous peoples have also hunted sea otters for food and fur. Marine mammals as food Marine mammals are a food source in many countries around the world. Historically, they were hunted by coastal people, and in the case of aboriginal whaling, still are. This sort of subsistence hunting was