In domesticated dogs, hair type is controlled by two different alleles. The allele for wire hair is (H) and the allele for smooth hair is (h). When two heterozygous dogs are crossed, what percentage of the offspring is expected to be homozygous for smooth hair? Ask Studybuddy (Login to use)Group of answer choices50%75%25%0%
Question
In domesticated dogs, hair type is controlled by two different alleles. The allele for wire hair is (H) and the allele for smooth hair is (h). When two heterozygous dogs are crossed, what percentage of the offspring is expected to be homozygous for smooth hair? Ask Studybuddy (Login to use)Group of answer choices50%75%25%0%
Solution
The question is asking about a Punnett square problem involving two heterozygous parents.
Here's how you solve it:
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Identify the genotypes of the parents. In this case, both parents are heterozygous, meaning they have one allele for wire hair (H) and one for smooth hair (h). So, their genotypes are Hh.
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Set up a Punnett square. This is a simple 2x2 grid used to calculate the probabilities of genotypes in offspring. Label one side of the grid with the alleles from one parent (H and h) and the other side with the alleles from the other parent (H and h).
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Fill in the Punnett square. Each box in the grid represents a possible genotype for an offspring. Fill in each box by combining the alleles from the corresponding row and column. In this case, the Punnett square looks like this:
| H | h ---|---|--- H | HH | Hh h | Hh | hh
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Count the number of each genotype. In this case, there is 1 HH (wire hair), 2 Hh (wire hair), and 1 hh (smooth hair).
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Calculate the percentage of offspring that are homozygous for smooth hair. This is the number of hh (smooth hair) boxes divided by the total number of boxes. In this case, it's 1/4, or 25%.
So, the answer is 25%.
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