Word: bacterias
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...chance that Mars may be the home of primitive living things something like bacteria, a soil sample in another chamber will be slightly moistened by a nutrient solution laced with carbon 14. The sample will be incubated, then tested to learn whether anything in the soil has consumed the nutrient and released waste gases containing the telltale carbon...
Commoner's work relies heavily upon a test devised by Dr. Bruce Ames of the University of California at Berkeley. Ames found that certain carcinogens were capable of causing mutations in bacteria. This suggested to Ames the possibility of using mutagenicity, the ability to cause mutations, which can be determined simply and quickly, as a test for carcinogenicity...
...determine the correlation, Commoner and his Washington University colleagues tested 92 chemical compounds on strains of the common bacteria Salmonella typhimurium, developed by Ames. Each compound was made up in three different concentrations and mixed with preparations made from seven different rat tissues (liver, kidney, brain, stomach, lung, spleen and blood); each of the mixtures was then added to culture dishes containing the Salmonella...
...results were dramatic. Of the 50 compounds that were known to be noncarcinogenic, only one, which happened to be a close chemical relative of a known carcinogen, caused the bacteria to mutate at a significant rate. Of the 42 other compounds, all known carcinogens, all but seven induced bacterial mutations by themselves. When the urine of rats that had been fed to three of the remaining compounds was placed in the culture dishes, it too produced mutations, suggesting that the chemicals, which may not cause cancer directly, are metabolized in the body into substances that do. With a slight change...
...organism which caused food poisoning on March 26 at South House, leaving more than 20 people ill and 4 hospitalized, was identified at state laboratories yesterday as a rare bacteria found in uncooked seafood...