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
Freshwater bivalve on a fish or salamander. Many species are utilized as sources of mother-of-pearl. Families: Order Veneroida The Veneroida is a large group of bivalve "clams", most of which are marine. However, several families occur in fresh and brackish waters. Families: Freshwater bivalve Freshwater bivalves are one kind of freshwater molluscs, along with freshwater snails. They are bivalves which live in freshwater, as opposed to saltwater, the main habitat type for bivalves. The majority of species of bivalve molluscs live in the sea, but in addition, a number of different families live in freshwater (and in some cases also in brackish