An animal that hides under a rock to avoid predators is responding to a(n) stimulus.

Christie's doctor recommends that she eat 40 grams of protein a day. she's already consumed 50% of her protein recommendation for the day. how many servings of the given snack should christie have to meet her daily protein recommendation?

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

Amylase is an enzyme found in the human digestive system. why do you think it was important to keep the enzyme temperature about 37 degrees celsius (98.6 degrees f)? describe what might happened the temperature decreased by 10 degrees celsius.