Black skin color is dominant to pink skin color in pigs. Two heterozygous black pigs are crossed.

What is the probability that the first and second offspring will have black skin?

Key Concepts

Dominant and Recessive Alleles

In genetics, alleles are different forms of a gene. A dominant allele, represented by a capital letter, masks the effect of a recessive allele, represented by a lowercase letter. In this case, the allele for black skin color is dominant over the allele for pink skin color. Therefore, any pig with at least one dominant allele will exhibit black skin.

Punnett Square

A Punnett square is a diagram used to predict the genetic outcomes of a cross between two organisms. It helps visualize the possible combinations of alleles from the parents. For two heterozygous black pigs (Bb x Bb), the Punnett square will show the probabilities of offspring having black (BB or Bb) or pink (bb) skin color, allowing us to calculate the likelihood of specific traits in the offspring.

Independent Assortment

Independent assortment is a principle of genetics stating that alleles for different traits segregate independently of one another during gamete formation. In this scenario, since the skin color trait is being considered, the probability of each offspring's skin color is independent of the others. Thus, the probability of both the first and second offspring having black skin can be calculated by multiplying their individual probabilities.