To determine the percent chance that their offspring will have unattached earlobes, we need to evaluate the Punnett square provided.
If one parent has attached earlobes (aa) and the other parent has unattached earlobes (AA), the possible combinations of their genotypes in the offspring will be as follows:
- 50% chance of offspring having attached earlobes (Aa)
- 50% chance of offspring having unattached earlobes (Aa)
Therefore, there is a 50% chance that their offspring will have unattached earlobes.