Principles of Biology : Laboratory

Lab 12 : Drosophila II

Theme: Look at the theme I gave you in Lab 7 and write a similar, short, concise theme for this lab.

Materials and Methods: "Biology Lab Manual" by The College Board, 2001. <cite correct page numbers for handling Drosophila (Lab 7 in the book)>

Results:  <Submit your data for the dihybrid F2 count on the Dihybrid Data Sheet.  The combined data is posted on the web. You can write: >

See combined class data at: http://www.siskiyous.edu/class/bio1/lab12/dihybrid.cross.xls

Analysis and Conclusion Section :

This lab does not include the lab book (except the reference in Materials and Methods). In this section I want you to briefly describe what this cross what about, what were the parental genotypes, what were the parental phenotypes? F1 generation? and F2 generation (from combined class data). Formulate your hypothesis for testing (hint: it is the 9:3:3:1 ratio of phenotypes) based on independent assortment of the two mutants. Then, clearly showing all your work, calculate the chi-squared statistic and apply it. Is the null hypothesis rejected or not rejected at alpha of 0.05 (the usual)?


Nov. 18, 7:30 p.m.