Answer:
because it permits certain movement of molecules in and out of the cell
Answer:
I saw this question on my recent test
B. Both were common governments for early river valley civilizations.
This was my answer and Got it right. Hope This helps you! :0) lol
Answer:
To get crude density, divide the total land area by the total population. You can see that when you measure a large area of land, the arithmetic density becomes meaningless because it “blends in” the urban population and masks the sparsely-inhabited areas with an average.
Answer:
c) No UV light until spring
Explanation:
According to research, chlorofluorocarbons also known as CFCs, are chemicals that are mainly responsible for the destruction of the ozone gas.
<em><u>This is all due to the interaction of different factors, and not only because of the presence of UV. </u></em>
In Antarctica, the ozone levels become significantly reduced during spring because of these chemicals that contain chlorine, producing a hole where cool air becomes trapped. This air produces clouds that are responsible of the release of chlorine from the CFCs, an extremely important process of the formation of an ozone hole. The more clouds there are, the more gases are released, and the worse the ozone hole will be in spring.
Because the sun rises and becomes more intense during spring, it degrades these gases and releases the free radicals of chlorine, which are highly detrimental for the ozone layer as they destroy numerous molecules of ozone. By the beginning of summer, there is a higher amount of ozone that comes from other areas which help fill the ozone hole.