Now, this is if we assume that no Crossing Over took place. But crossing over does normally take place. And that's exactly what we discussed in part three. Suppose that the actual F two distribution was as follows instead of having this hypothetical distribution because crossing over does take place we produce this distribution. So notice that now not only do we have the gray and wingless and the black and winged as we have in this case we also have the gray winged and the black winged. And these two here are actually the recombinant offsprings and they are produced as a result of crossing over as a result of the production of recombinant chromosomes.