Question

The F1 offspring of a cross has been provided for you. It is your job to work backwards in order to determine the genotypes, the genetic makeup, of BOTH parents that produced each cross. More specifically, what parental genotypes would give you these possible genotype combination?

Answer 1

To fill the Punnett Square we must place the alleles from one of the parents horizontally oriented on the top of a 3x3 diagram, and the alleles from the other parent vertically oriented on the left border of the diagram. After that, we must cross each one of the alleles from one parent with the alleles of the other, positioning the result of those crossings (Ee) in the blank space where those alleles meet. Therefore, we must look at the combinations and extract the allele that appears in the same line or in the same column, as follows:

Therefore, the parental genotypes are: EE x ee.