In Drosophila melanogaster, the recessive allele for the sepia locus (se) causes flies to have very dark colored eyes. The reces
sive allele at the apterous (ap) locus causes the fly to lack wings. A male from a true breeding line of sepia eyed, apterous flies (line A) is crossed to a female from a true breeding line of red eyed, winged flies (the "wild type" line B) to create an Fl:
Next, a female from the Fl is crossed to a male from line A.
The phenotypes of 1000 progeny from this test cross were scored as follows:
Freshwater is a precious resource on the Earth's surface. It is also home to many diverse fish, plant, and crustacean species. The habitats that freshwater ecosystems provide consist of lakes, rivers, ponds, wetlands, streams, and springs.
