Where are stems cells found?
What is the function of a stem cell?

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.

This map shows how climate change might affect precipitation patterns in the great plains of the united states by the end of this century. brown shoes a decrease in percipitation, and blue shows an increase. the maps differ based on the predictive levels of green house emissions. the maps shows that northern area should get a. more pracipations regardless of emmissions b. less pracipation, regardless of emmissions levels c. more precipitation, but only when emission levels. southern areas show a. more pracipations regardless of emmissions b. less pracipation, regardless of emmissions levels c. more precipitation, but only when emission levels. to use these maps to prepare for natural disasters in the great plains, scientist need to ask? a. how many tons of emissions were used at the basis of the map. b. which types of fossil fuels are used in the great plains c. if you think the above is wrong it's probly c the question is cut off

Environmental science are unconsidered with methods to preserve natural resourcesa. trueb. false