How are dna and rna molecules alike? a. they are both double stranded. b. they both contain nitrogen bases. c. their nitrogen bases always pair a - t and c - g. d. they are found in the nucleus and at the ribosomes?

She planned to observe the flowers for the next five days for an hour at the same time each afternoon. then she wou the data in a multiple line graph to compare the number of bees that visited each flower. which statement best descr data in this investigation?

Why do you think the puppy litter was all dark-haired?

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