The cellulose is flexible and allows cells to increase in size. the provides considerable strength for the plant cell. the main component of the cell wall is lignin. in plants, is a metabolite that hardens the wall. plant cell wall polysaccharides are made of repeating molecules.

Babies with very low or very high weight are less likely to survive .

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

Animals that have thick fur and ae able to store large amounts of body fat live where ?