UT BIO 325L - Homework5[key]Spring14 (5 pages)

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Name Lab room day time TA name Patterns of inheritance This semester you are working to figure out the pattern of inheritance of 2 different lines of flies This task and its associated statistical tests are much easier if you can recognize or reason through the patterns you are seeing Last week you were asked to consider the outcomes in the F2 generation and you will do the same this week For the following questions you will get the safest results by doing the punnet square rather than just guessing When in doubt write it out 1 White eyes can e due to the combination of two mutations which eliminate both pigment types normally found in the Drosophila eye Assume for this question that the two mutations are autosomal recessive and not linked a 0 5 What are the genotypes of the P generation Recall how the cross was set up in lab Based on the above information you should be able to determine which two genes are involved Since they are unlinked this should be brown with scarlet brown is on chromosome 2 scarlet on 3 P x bw bw st st they can also write out all the chromosomes as P x Y bw bw st st b 0 5 Write the genotypes of the expected F1 progeny F1 bw st c 1 Write the Punnet square showing the genotypes expected in the F2 progeny Be careful here Remember that maternal and paternal contributions are noted specifically even if certain genotypes are ultimately equivalent A Punnet square is best here since the maternal paternal chromosome tracking gets complicated Paternal gametes are typically shown on the row across the top with maternal along the left column but as long as they specify it can be done the other way bw st bw st bw st bw st bw bw bw bw bw st bw bw st st st bw st st st bw st st bw st bw st bw bw st bw st st bw bw st st d 0 5 What are the phenotypes AND phenotypic ratios expected in the F2 progeny The phenotypes will be 9 brick red eyes wild type 3 bright red eyes 3 brown eyes 1 white eyes They can also use percentages for their answer e 0 5 Write the