ANTIBIOTIC SUSCEPTIBILITY TESTING. Bacteria demonstrate two kinds of resistance to antibiotics, namely intrinsic resistance and acquired resistance. Intrinsic resistance means that the species was resistant to an antibiotic even before its introduction.
Radiation is naturally present in our environment, as it has been since before the birth of this planet. In addition, radiation can be produced artificially, as in medical x-rays and microwaves for cooking. Nonetheless, most people are not aware of all the natural and man-made sources of radiation in our environment.
The 1986 Chernobyl disaster triggered the release of substantial amounts of radioactivity into the atmosphere in the form of both particulate and gaseous radioisotopes. It is one of the most significant unintentional releases of radioactivity into the environment to present.