Question

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. Which describes the genotypes of their offspring?
100 percent Ee
100 percent unattached earlobes
100 percent ee
100 percent attached earlobes

Answer 1

Its A or 100% Ee

Step-by-step explanation:

edge 2022

Answer 2

100 percent Ee

Step-by-step explanation:

This is a cross involving a single gene coding for attachment or not of earlobes. The allele for unattached earlobes (E) is dominant over the allele for attached earlobe (e). This means that allele E will always mask the phenotypic expression of e in a heterozygous state.

A parent that has same alleles for unattached earlobes i.e. EE is crossed with a parent that has same alleles for attached earlobes i.e. ee. In this cross, all of the offsprings will have a heterozygous genotype, Ee because gametes E and e will be produced respectively by each parent.

Hence, since all of the offsprings will have an Ee genotype, it means 100% of their offsprings will have Ee (HETEROZYGOUS).