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Genetics as it applies to evolution, molecular biology, and medical aspects.

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Postby taata » Thu Jul 07, 2005 11:56 pm

The wild type (normal) fruit fly, Drosophila melanogaster, has straight wings and long bristles. Mutants have been isolated that have curled wings or short bristles. Consider the five crosses given in the table below.

Cross Number of progeny
Straight wings, long bristles Straight wings, short bristles Curled wings, long bristles Curled wings, short bristles
1 Straight, short X straight, short 30 90 10 30
2. Straight, long X straight, long 120 0 40 0
3 Curled, long X straight, short 40 40 40 40
4 Straight, short X straight, short 40 120 0 0
5 Curled, short X straight, short 20 60 20 60

a) For each mutation (curled wings, short bristles), determine whether the mutant allele is dominant or recessive. State which crosses support your answer.
b) Devise a notation system (symbols) to represent the different alleles for each character.
c) Determine the genotypes of each of the parents in each cross. :cry: :cry: :cry:
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Postby mith » Fri Jul 08, 2005 1:33 am

I'll give you a hint for b....there's really no wrong answer as long as it's composed of letters with the dominant being designated by capital letters.
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