It is believed that mitchondrial DNA (mtDNA) follows a non-Mendelian inheritance pattern. It is hypothesized that all mitochondria are inherited from the egg, and the sperm cell does not contribute mitochondria to the fertilized egg.
Which of the following experimental procedures would be the best method to test this theory?
O Test the mtDNA of random flies to determine if all flies have the same mtDNA
Mate a specific fly, and test the mtDNA of both a male and female offspring to see if the mtDNA is identical to the
mother.
Mate a specific female fly, and select a male and female offspring. Mate them with each other and test the mtDNA
of the “grandchildren."
Mate a female fly, and mate the offspring with unrelated flies with different mtDNA. Test the mtDNA of the
"grandchildren."

Which type of organism is missing from the food web seen in the illustration? primary consumers decomposers primary producers secondary consumers

After fertilization, which type of cellular division is responsible for the growth and development of a complex, multicellular organism?

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.