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1. mineral a scratches minerals e and i, but it can be scratched by mineral j.
2. mineral c can be scratched by every other mineral.
3. mineral e can scratch mineral i.
4. mineral f can scratch only mineral c.
5. mineral b can scratch mineral f, but it can be scratched by all the other minera
6. mineral h can scratch every other mineral.
7. mineral d can be scratched only by mineral h.
8. mineral g can be scratched by minerals hand d; it can scratch mineral j.
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for  example, forests have higher evapotranspiration than other ecosystems,  such  as grasslands, because of their deeper roots and greater leaf area. thus forests have a net moistening effect on the atmosphere and become a moisture source for downwind ecosystems.

many other transport proteins, often called pumps, move materials against a concentration gradient. active transport drives molecules across a membrane from a region of lower concentration to a region of higher concentration. this process, shown in figure 5.1, uses transport proteins powered by chemi- cal energy.