There are two classes of membrane transport proteins—carriers<span> and </span>channels<span>. Both form continuous </span>protein<span> pathways across the lipid bilayer. Whereas transport by </span>carriers<span> can be either active or passive, solute flow through </span>channel proteins<span> is always passive.</span>
When transitioning from a mostly rural to a mostly urban society, it is important to keep sustainability in mind. Try to find ways in which the most energy is conserved, which will increase employment and lower revenue and pollution.
I think A but I'm not totally sure!! Good luck.
Answer:Increase in ambient global temperatures.
Recyling energy to be used again
Regulation of oxygen and carbon dioxide levels
An increase of erosion and siltation along waterways
Explanation:
Conservational biologists think about the preservation of ecosystem by maintaining the environment in a human control way.
Increase in ambient global temperatures.: The humans must prevent the increase in global temperature worldwide by preventing the rise of greenhouse gases which can lead to global warming worldwide.
Recyling energy to be used again: The sources of energy like wood, waste water can be recycled again for reutilization.
Regulation of oxygen and carbon dioxide levels.: The oxygen and carbon dioxide levels must be regulated. As oxygen is the basic requirement for respiration. The increase in carbon dioxide levels due to human activities is likely to cause respiratory diseases and health hazards in living beings.
An increase of erosion and siltation along waterways.: The erosion and siltation will likely to deposit nutrients and debris which may either contaminate the waterway or may cause eutrophication.