University of Texas, San Antonio BIOLOGY 1404 Lab 8 - Genetics Post-Lab Assignment

Identifying Inheritance Patterns in a Drosophila Dihybrid Cross

Cross A

Table 1A. Phenotypes and Genotypes of the Parental Stocks and F1
progeny


Card Cross
Phenotype Genotype
Number = 8

True-Breeding
Parental Male Wild Type Body, Ebony e-e- C+ C+


True-Breeding
Parental Female Wild Type Body, Curley e+e+ C- C-



F1 male Wild Type Body, Curley e+e- C+ C-



F1 female Wild Type Body, Curley e+e- C+ C-



Which live culture contains the trait for the parental male ? A


Which live culture contains the trait for the parental female? G


Which traits are dominant? Wild Type Body, Curley Wings


Which traits are recessive? Ebony Body, Wild Type Wings


Are any traits sex linked? No

, Table 2A. Punnett Square for F2 Generation

Eggs

Sperm
e+C+ e+C- e-C+ e-C-


e+C- e+e+C+C+ e+e+C+C- e+e-C+C+ e+e-C+C-


e+C- e+e+C+C- e+e+C-C- e+e-C+C- e+e+C-C-


e-C+ e+e-C+C+ e+e-C+C- e-e-C+C+ e-e-C+C-

e-C- e+e-C+C- e+e-C-C- e-e-C+C- e-e-C-C-

, Identifying Inheritance Patterns in a Drosophila Dihybrid Cross

Cross A


Table 3A. Predictions and Observations of the F2 generation for a Dihybrid Cross
Predicted
Expected Frequency Observed Number
Phenotype
From Punnett From Punnett
From Cards
Square Square
Wild Type Body, Curley 9/16 93
Wings

Wild Type Body, Wild
3/16 36
Type Wings
Ebony Body, Curley
3/16 31
Wings
Ebony Body, Wild Type
1/16 12
Wings



Total ___172___