When the heated part of the mantle rises through the cooler part , this is an example of Convection.
Answer:
Molecules which move against the concentration gradient across the cell membrane employ the mechanism of active transportation.
Explanation:
Normally, permitted molecules moves across the cell membrane of the cell by the process of diffusion and osmosis. This is used when molecules move from hypertonic region to hypotonic region (if ions) and hypotonic to hypertonic (if water). This is a passive transportation which do not require the expense of energy from the cell.
In contrast, when molecules move in or out of the cell against their concentration gradient, that is ions moving from hypotonic region to hypertonic region, they implore the expense of energy in form of adenosine triphosphate (ATP), and the involvement of the membrane carrier proteins. This is called active transport.
Answer: C.
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Answer:
The most effective experimental approach to assess the effects of elephant impact on vegetation is to assess plant responses under differences in elephant density. It is important that other factors, such as soils or habitat structure are held constant so that the only factor which varies is elephant density.
Explanation:
source: Studying Elephants icun.org
