When materials diffuse across a membrane, they move from of concentration to an area of concentration along the concentration gradient.

Read the following scenario to answer the following question. 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. when most populations of a wide-ranging amphibian species are lost and the few remaining populations are widely separated, we expect to see that a. the founder effect becomes increasingly important b. microevolution no longer occurs c. gene flow between populations is reduced d. artificial selection becomes a greater factor in microevolution

Which number represents a basic ph, 4 or 9? numerical answers expected! answer for blank 1: i'll give

Agenetically engineered corn plant is approved for agricultural use. the plant produces pollen that can make its own toxins. these toxins protect the corn plant against pests and no longer require the application of chemical pesticide. what is a likely impact on the farmer of growing such a variety of corn? a- the financial costs for the farmer would be lowered since less crops would be lost to pests. b-the financial costs for the farmer would be lowered since more crops would be lost to pests. c-the farmer may be held responsible for increasing chemical pollution. d-the farmer's expenses for pest control would increase due to an increase in bee population.