"the student predicted that the contractile vacuole would contract fewer times in one minute in a solution that had a higher concentration of salt than that found in typical pond water. this prediction is most likely
(1)correct, because a high concentration of salt in the environment will force water into the cell, causing the contractile vacuole to pump
(2)incorrect, because salt would be entering the cell, and the contractile vacuole would have to pump it out
(3)incorrect, because the concentration of salt in the environment should not affect a cell
(4)correct, because water would be moving out of the cell into the salt solution"

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

Onsider the paragraph above. what is one chemical property of water? a) water is a polar molecule. b) water is the universal solvent. c) water reacts with group 1 metals. d) water has a high specific heat capacity.

Which box will not accelerate? 4 newtons 4 newtons 4 newtons 25 kg 4 newtons 15 newtons 10 kg 30 newtons 40 newtons 50 kg 30 newtons 30 newtons