Fly Lab Assignments 1-4
INSTRUCTIONS
Answer questions on a separate sheet of paper. Be sure to answer all parts of each question. Make sure you number all questions EXACTLY as they are numbered on this worksheet. This assignment will be turned in at the beginning of class before the quiz. Late assignments WILL NOT be accepted.
DON’T FORGET: Fly lab/epistasis assignment on pgs. 41-42 in lab manual is also due at the beginning of lab.
Assignment 1: Getting to Know FlyLab: Performing Monohybrid, Dihybrid, and Trihybrid Crosses
1.c. Based on what you know about the principles of Mendelian genetics, predict the phenotypic ratio that you would expect to see for the F1 offspring of this cross and describe the phenotype of each fly.
1.d. Are the phenotypes of the F1 offspring what you would have predicted for this cross? Why or why not?
1.g. What phenotypic ratio do you expect to see in the F2 offspring?
1.h. State your null hypothesis, chi-square value, degrees of freedom and level of significance? Was your ratio rejected or not rejected?
1.j. What did you discover to be the correct phenotypic ratio for this experiment? Was this what you expected? Why or why not? What do the results of this experiment tell you about the dominance or recessiveness of the sepia allele for eye color?
2. What effect, if any, does this have on the results produced and your ability to perform chi-square analysis on these data? If any of your crosses do not follow an expected pattern of inheritance, provide possible reasons to account for your results.
3. Describe the phenotypes that you observed in both the F1 and F2 generations of this cross. How does the observed phenotypic ratio for the F2 generation compare with your predicted phenotypic ratio? Explain your answer.
4. Develop a hypothesis to predict the results of this cross and describe each phenotype that you would