After you eat a meal your blood glucose levels rise. Cells in the pancreas sense the increase in glucose and release insulin. Insulin binds to cell surface receptors that activate molecules inside the cell leading to the insertion of glucose transporters in the cell membrane and the transport of glucose from the extracellular space into the cell. This results in decreased in blood glucose levels. The decrease is sensed by the pancreatic cells and insulin release is stopped. What kind of system is represented by the series of events described above?

The images show the wings of a bat and a bee. from this evidence, what can you conclude about the evolutionary relationship between these organisms? a. the wing structures of the bat and the bee are different, indicating they didn’t inherit wings from a common ancestor. b. the wing structures of the bat and the bee are different, indicating they inherited wings from a common ancestor. c. the functions of bat wings and bee wings are the same, indicating they obtained wings from a common ancestor. d. the functions of bat wings and bee wings are different, indicating they didn’t obtain wings from a common ancestor.

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

How is mitosis different in plants and animals? a. in animals, the cell membrane pinches together. b. in plants,the dna is one circular chromosomes. c. in plants, there are no sister chromatids. d. in animals, a new cell wall forms.