What will be the result of the first filial generation (F1) and the second filial generation (F2) of a mono-hybrid cross between pure line normal-winged Dro...

In a mono-hybrid cross, two pure breeding parents that differ in only one characteristic are crossed to produce the first filial generation (F1). When the gene for normal wings is dominant over the gene for short wings, the F1 generation resulting from the cross between pure line normal-winged Drosophila flies and pure line short-winged flies will all have normal wings because they will inherit the dominant gene from the normal-winged parent. In the second filial generation (F2), the offspring resulting from the cross of F1 individuals, the dominant and recessive traits will segregate in a 3:1 ratio. This means that approximately three-quarters of the F2 flies will have normal wings, and one-quarter will have short wings. Therefore, the correct answer is "F1 flies all normal-winged and three-quarters of F2 flies are normal-winged".