Question

the punnett square predicts the ratio of genotypes in the offspring based on the genotypes of the parents. which punnett square represents a cross between a mom who is heterozygous for dimples and a dad who is homozygous for no dimples?

Explanation:

Step1: Determine the parents' genotypes

Let \(D\) represent the allele for dimples and \(d\) represent the allele for no dimples. The mom is heterozygous for dimples, so her genotype is \(Dd\). The dad is homozygous for no dimples, so his genotype is \(dd\).

Step2: Analyze the first Punnett square

The first Punnett square has the dad's alleles as \(D\) and \(D\) (which is incorrect since the dad is homozygous \(dd\)).

Step3: Analyze the second Punnett square

The second Punnett square has the mom's alleles (\(D\) and \(d\)) on the top and the dad's alleles (\(d\) and \(d\)) on the side. When we cross \(Dd\times dd\):

• For the first row: \(D\times d = Dd\) and \(d\times d=dd\)
• For the second row: \(D\times d = Dd\) and \(d\times d = dd\)

Answer:

The second Punnett square (with mom's alleles \(D\) and \(d\) on the top and dad's alleles \(d\) and \(d\) on the side) is the correct one.