Question

Some dog breeds have two different alleles for tail length, one for long tails and one for short tails. If one of these dogs is heterozygous for tail length, they have a medium-length tail. What type of genetic inheritance does this represent?

Answer 1

The type of genetic inheritance that causes dogs with heterozygous alleles for tail length to have a medium-length tail is known as incomplete dominance.

Step-by-step explanation:

The genetic inheritance pattern described where dogs with heterozygous alleles for tail length have a medium-length tail represents incomplete dominance. This is different from the complete dominance, where the dominant allele masks the recessive one, leading to the heterozygote expressing only the dominant trait. In the case of incomplete dominance, neither allele is dominant, and the heterozygous phenotype is somewhere in between the homozygous dominant and recessive phenotypes.

Polygenic inheritance is another concept, but it does not apply to the scenario with the dog's tail. This type of inheritance involves many genes contributing to a single phenotype, often resulting in a continuous range of variation, like human height. Additionally, codominance is a pattern where both alleles in a heterozygous individual are fully expressed, such as in human blood types, but this is not the pattern observed in the dog's tail length example.

Answer 2

This type of genetic inheritance represents incomplete dominance.

Step-by-step explanation:

This type of genetic inheritance represents incomplete dominance. In incomplete dominance, the heterozygous phenotype is an intermediate between the homozygous dominant and homozygous recessive phenotypes. For example, if one parent passes a long tail allele (L) and the other parent passes a short tail allele (S), the heterozygous offspring will have a medium-length tail.