Afamily of giraffes is living on the african savannah. the trees on the savannah are very tall and scattered. during the dry season, the giraffes must be able to reach the leaves of these trees for food. a mother giraffe gives birth to two calves. calf a has inherited a mutation that will make his neck longer than his mother when he is full grown. calf b, on the other hand, has inherited a mutation that will make his neck shorter than his mother. from this story, which of the following statements can be inferred about genetic mutations? mutations cannot affect an individual because they can never be passed to the next generation. b. mutations can be harmful at first, but the tall trees will cause calf b's neck to grow longer than it would otherwise. c. mutations may result in a favorable change that improves an organisms's ability to survive or an unfavorable change that harms an organism's ability to survive. d. mutations are always harmful to an individual because they are changes in the dna code.

Which is an example of a decomposer? a. bear b.algae c.grass d.bacteria d bacteria

What evidence supports the law of conservation of energy? a) mechanical energy is converted to chemical energy during photosynthesis. b) oxygen is made from the breakdown of carbon dioxide during photosynthesis. c)energy is absorbed by chlorophyll and becomes chemical energy during photosynthesis. d)the sun gives off light energy that is absorbed by plants.

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.