Discussion:
Dihybrid test cross
Consider the following two genotypes: AABB , aabb where A and B are dominant and a and b are recessive:
1) What is the genotype of the F1 progeny from an AABB x aabb cross?
2) Construct a Punnet square of the F1 self cross (i.e. F1 x F1). What are the genotypic ratios from this testcross? What are the phenotypic ratios?
3) Construct a Punnet square of the F1 genotype with the AABB parental. What are the genotypic ratios from thsi cross? What are the phenotypic ratios?
4) Construct a Punnet square of the F1 genotype with the aabb parental. What are the genotypic ratios? What are the phenotypic ratios?
5) If you had an organism that was A- B- and wanted to determine its exact genotype, which cross would you use? Explain your answer.