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.
Nuclear Radiation. The release of radiation is a phenomenon unique to nuclear explosions. There are several kinds of radiation emitted; these types include gamma, neutron, and ionizing radiation, and are emitted not only at the time of detonation (initial radiation) but also for long periods of time afterward (residual radiation).