Determine the probability of a couple having a child with a widow's peak if the conditions are as follows: The gene for widow's peak follows strict autosomal dominant-recessive inheritance. Widow's peak (W) is dominant, and no widow's peak (w) is recessive. The genotype of the mother is Ww, and the genotype of the father is ww.

Verified step by step guidance

1. Identify the genotypes of the parents: Mother is Ww and Father is ww.
2. Set up a Punnett square to determine the possible genotypes of the offspring.
3. Place the mother's alleles (W and w) on the top of the Punnett square and the father's alleles (w and w) on the side.
4. Fill in the Punnett square by combining the alleles from each parent to show the potential genotypes of the offspring.
5. Determine the probability of each genotype and identify which genotypes correspond to a widow's peak phenotype.

Key Concepts

Autosomal Dominant and Recessive Inheritance

Autosomal inheritance refers to the transmission of genes located on the autosomes, which are the non-sex chromosomes. In this context, widow's peak (W) is an autosomal dominant trait, meaning that only one copy of the dominant allele is needed for the trait to be expressed. Conversely, the recessive allele (w) requires two copies to manifest the trait. Understanding this inheritance pattern is crucial for predicting the probability of offspring traits.

Genotype and Phenotype

The genotype refers to the genetic makeup of an individual, specifically the alleles they possess for a particular trait. In this case, the mother has a genotype of Ww (heterozygous) and the father has a genotype of ww (homozygous recessive). The phenotype is the observable expression of the genotype, which in this scenario relates to whether the child will have a widow's peak or not. Analyzing genotypes helps in determining the likelihood of specific phenotypes in offspring.

Punnett Square

A Punnett square is a graphical tool used to predict the genotypes of offspring from parental genotypes. By arranging the alleles of each parent along the axes of a grid, one can visualize all possible combinations of alleles in the offspring. In this case, creating a Punnett square with the mother's Ww and the father's ww genotypes will reveal the probabilities of their child inheriting a widow's peak, aiding in understanding genetic inheritance.