Ribosomes provide the scaffolding on which trnas interact with mrna during translation of an mrna sequence to a chain of amino acids. a ribosome has three binding sites, each of which has a distinct function in the trna-mrna interactions. drag the appropriate trnas to the binding sites on the ribosome to show the configurationimmediately beforea new peptide bond forms. note that one of the binding sites should be left empty.

Ageologist determines that a sample of a mineral cant be scratched by a steel nail but can be scratched by a masonry drill bit based on this information the sample mineral has to be softer than

Astudent drew the following flowchart to show the movement of nutrients. soil → roots → plants →? where does nitrogen go next? a. directly into nearby animals as nutrition b. directly into aquifers through condensation c. directly into the air through evaporation d. directly into nearby plants during fixation

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