What is the function of the cholesterol molecules in a cell membrane?
a. they make it thicker.
b. they make it porous.
c. they make it more fluid.
d. they make it less flexible.

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

Research question: why are the carrots that grew on the left side of the garden larger than the carrots that grew on the right side of the garden? which hypothesis is based on this research question? a comparison of people with gardens to people without gardens will show who is likely to live longer. b. carrots are thought to be good for your eyesight and should be eaten regularly. c. carrots that are provided lots of sunlight grow to a larger size than carrots grown in the shade. d. eating fresh vegetables every day is a healthy thing to do.

2polnis which of the following is an advantage of an in vitro experiment?me