Unattached earlobes is a dominant trait, e. a parent who is homozygous for unattached earlobes is crossed with a parent who is homozygous for attached earlobes. what is the genotypic ratio of their offspring? a. 100 percent ee b. 100 percent unattached earlobes c. 100 percent ee d. 100 percent attached earlobes

A. 100 percent Ee

Explanation:

The genotype of the parent who is homozygous for unattached earlobe would be EE.

The genotype for the parent who is homozygous for attached earlobe would be ee.

When a cross is made between these two then ,

EE X ee ---> Ee Ee Ee Ee

The 4 offsprings produced as a result of this cross will all have the genotype Ee.

Since E (unattached earlobe) is dominant over attached earlobe (e) the heterozygous Ee will have unattached earlobe.

Therefore, the genotypic ration would be 100% Ee.

See the attached punnet diagram for the cross.