Question

Goats can either be pulled or horned. The pulled, or no horn, trait (P) is dominant to the horned (p) trait. Another trait in goats are wattles, which are hair covered structures on their necks. Even though most goats do not have wattles, having wattles (W) is dominant to not having wattles (w). A breeder crosses a pulled, wattled male goat with a pulled, wattled female goat. Some of the offspring have horns and no wattles. 1) Knowing this, what are the genotypes of the male and female parental goats? 2) Perform a cross of the parental genotypes to find the phenotypic ratios of the F1 generation.

Answer 1

The genotype of each parent goat is PpWw, and by performing a Punnett square cross, the phenotypic ratios of the F1 generation are approximately 9:3:3:1 for the traits pulled horns and wattles.

Step-by-step explanation:

Given that some offspring resulted with horns and no wattles, we can infer that both parents are heterozygous for both traits.

Therefore, the genotype of each parent would be PpWw.

To find the phenotypic ratios of the F1 generation, we use a Punnett square which predicts the outcomes of genetic crosses.

When we cross the genotypes PpWw × PpWw, the Punnett square shows a ratio of 9:3:3:1.

This means in a group of 16 offspring, approximately 9 will have both pulled horns and wattles (PW), 3 will have pulled horns without wattles (Pw), 3 will have horns but have wattles (pW), and 1 will have horns and no wattles (pw).