Frogs have lungs for breathing, but they also absorb dissolved oxygen directly through their skin. this allows respiration to occur when they are underwater. when they are on land, mucus keeps their skin moist to continue to absorb dissolved oxygen from the air. which statement about water is best illustrated by this example?

a) liquid water can transport nutrients
b) water breaks down into oxygen molecules for respiration
c) water is found in every cell of an animal’s body
d) liquid water is necessary for plants and animals

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

What is the 77 element on the periodtic table

What molecule contains an organisms genetic material, passed down from parents to their offspring