Bacteriophages are viruses that infect bacteria. in an experiment, bacteriophages were labeled with either radioactive phosphorus or radioactive sulfur. the labeled bacteriophages were incubated with bacteria for a brief amount of time and then removed. the infected bacteria cells were found to contain significant amounts of radioactive phosphorus but not radioactive sulfur. based on the results of the experiment, which of the following types of molecules did the bacteriophages most likely inject into the bacteria cells? (a) simple carbohydrate (b) amino acid (c) dna (d) polypeptide

Often, caries will develop in an area of the tooth that's not readily accessible. which cavity preparation form defines this? a. retention b. resistance c. outline d. convenience

Over the past 60 years, many amphibian species have experienced significant population declines and some species have become extinct. scientists suspected that local human activities such as the destruction of wetlands, regional pollution, and deforestation were the main reasons for these losses. however, research over the past 20 years reveals significant amphibian population declines in protected areas of the world, such as nature preserves and parks. these global declines suggest widespread problems including increased ultraviolet radiation, acid rain, and disease. in switzerland, for example, 14 of the 20 native amphibian species are threatened with extinction. chytridiomycosis is a fungal disease first identified in 1998 as a cause of massive amphibian deaths. in some severely impacted populations, a few individuals have survived, perhaps because of some natural resistance. if these resistant individuals continue to survive and prosper, new resistant populations might emerge. this would be an example of the founder effect artificial selection genetic drift natural selection sexual selection

How do cells grow and reproduce to maintain homeostasis?