Which of the following is primarily responsible for limiting the number of trophic levels in most ecosystems? Energy transfer between trophic levels is usually less than 20 percent efficient. Nutrient cycling rates tend to be limited by decomposition. Many primary and higher-order consumers are opportunistic feeders. Decomposers compete with higher-order consumers for nutrients and energy.

i do not know and i have a 100 in this class

well we can't tell you because we cant see the time give a screen shot or something.

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.

it marks things for degradation via the proteasome. it alters there celluar location.