Imagine that horn color in Hodags (folkloric creatures of Wisconsin)is controlled by a single gene.You cross an orange-horned Hodag with an ivory-horned Hodag and get an F₁.Numerous offspring are produced,all with pale orange horns.You then cross two F₁ individuals.What phenotypic ratio would you expect in the F₂ generation? A)9 bright orange: 6 light orange: 1 ivory B)1 bright orange: 2 light orange: 1 ivory C)3 bright orange: 1 ivory D)1OO: 2OI: 1II E)3OO: 1 II

Question

Quizplus · Accepted Answer

From the initial cross, we can deduce that orange horns (represented by the letter "S") are dominant over ivory horns (represented by the letter "U"). Each parent contributed one "S" allele and one "U" allele to the offspring, resulting in an F1 generation of F₁. In this generation, all individuals have pale orange horns because the "B1" allele (which determines horn brightness) is recessive. When two F1 individuals are crossed, we can use a Punnett square to determine the genotypic and phenotypic ratios of the F2 generation. Since each parent can produce four gamete types (FS1B1, FS1B0, FU1B1, FU1B0), we end up with sixteen possible offspring genotypes: FS1B1 x FS1B1: 1/16 (bright orange) FS1B1 x FS1B0: 2/16 (2 bright orange: 2 light orange) FS1B1 x FU1B1: 1/16 (ivory) FS1B1 x FU1B0: 2/16 (1 bright orange: 1 ivory) FS1B0 x FS1B0: 1/16 (no horns) FS1B0 x FU1B1: 2/16 (1 light orange: 1 ivory) FS1B0 x FU1B0: 1/16 (no horns) FU1B1 x FU1B1: 1/16 (ivory) FU1B1 x FU1B0: 2/16 (2 light orange: 2 ivory) FU1B0 x FU1B0: 1/16 (no horns) From this table, we can see that the phenotypic ratio of the F2 generation is 1 bright orange: 2 light orange: 1 ivory, which corresponds to choice B.

Imagine That Horn Color in Hodags (Folkloric Creatures of Wisconsin)is