Cattle Genetics: Let's Unravel the Mystery of Horn Length!

What are the most likely genotypes of the parents?

In cattle, the allele for short horns () is dominant over the allele for long horns (s). Two short-horn cows are bred and produce four offspring. Three have short horns and one has long horns.

Answer:

The most likely genotypes of the parents are either A. Ss and Ss or C. SS and Ss.

Let's dive into the fascinating world of cattle genetics to understand how the horn length trait is inherited. In this scenario, we are dealing with a dominant-short horns allele () and a recessive-long horns allele (s).

When two short-horn cows are bred, the possible genotypes for the parents could be SS and Ss. This pairing would result in the following Punnett square:

Punnett Square:

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| S | s |

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| S | SS | Ss |

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| S | SS | Ss |

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From this Punnett square, we can see that the offspring could have genotypes of SS, Ss, or ss. In this case, three offspring have short horns, so the most likely genotypes of the parents are Ss and Ss, or SS and Ss.

It's truly amazing how genetics plays a role in determining physical traits in animals like cattle. Understanding the principles of dominant and recessive alleles can help us predict the outcomes of genetic crosses.