Which of the following scenarios are examples of positive-feedback mechanisms? check all that are correct.
deforestation near the sahara desert causes the soil to be exposed. exposed soil evaporates moisture more readily. insufficient moisture leads to the death of trees.
a warmer atmosphere causes more evaporation. more water vapor in the atmosphere leads to more cloud cover, which reflects more incoming solar radiation back to space and cools the surface.
a warmer atmosphere causes more evaporation. water vapor is a greenhouse gas, so this increases the temperature.
earth warms and radiation cools earth, much like a warm cup of coffee cools down if you let it sit on a table.
warmer temperatures cause snow to melt. this makes the ground darker, allowing more solar radiation to be absorbed. the warmer ground warms the atmosphere.

To answer this question, researchers studied populations of the dusky salamander (desmognathus ochrophaeus) living on different mountain ranges in the southern appalachian mountains. the researchers tested the reproductive isolation of pairs of salamander populations by leaving one male and one female together and later checking the females for the presence of sperm. four mating combinations were tested for each pair of populations (a and b)—two within the same population (female a with male a and female b with male b) and two between populations (female a with male b and female b with male a). the proportion of successful matings for each mating combination was measured. for example, when all the matings of a particular combination were successful, the researchers gave it a value of 1; when none of the matings were successful, they gave it a value of 0. then the researchers calculated an index of reproductive isolation that ranged from 0 (no isolation) to 2 (full isolation). the reproductive isolation value for two populations is the sum of the proportion of successful matings of each type within populations (aa + bb) minus the sum of the proportion of successful matings of each type between populations (ab + ba). the table provides data for the geographic distances and reproductive isolation values for 27 pairs of dusky salamander populations.

What is the role of the phospholipid belayer in cellular transport in living cells

What are they five steps of cloning?