flies
... Rather than feeding on fresh fruits, these flies only feed on the yeast that grows on rotting fruit. These flies have played a very important role towards medical science. These flies have also helped with the understanding the heredity of genetics and understanding the transmission of mutations and genes from parent to offspring. Fruit flies are often used as test animals due to its cheapness, fast reproductive ability, and its size. Because of this we know more about the biology of fruit flies than any other animal. Scientist have found 61% of human genetic diseases in fruit flies (Little People with Wings.) In this experiment two different crosses were performed using F1 (first generation) flies. ... sepia eyed flies are predicted to have a 3:1 ratio while the red vs. white eyed flies are predicted to have a 1:1:1:1 ratio. ... sepia eyed flies. Expected phenotypes: F2 flies SE se SE SEse SEse Se SEse sese Red eyed vs. ... Expected phenotypes: F2 flies Xw+ Xw Xw+ Xw+xw+ Xw+xw Y Xw+Y XwY Materials and Methods To perform these two different crosses culture tubes were made into which the fruit flies would breed.