Answer:
Mutations and sexual reproduction increase genetic variation in a population. Natural selection occurs when environmental pressures favor certain traits that are passed on to offspring. ... Individuals may mutate, but natural selection acts by shifting the characteristics of the population as a whole.
Explanation:
Mitochondria is the part responsible for making the ATP for the cells.
Important factor defining the desert biomes is its tendency to lose water by evaporation, and this potential for water loss exceeds the annual rainfall and defines what organism can live in there.