Download Polygenic Inheritance Questions

Polygenic Inheritance Questions
Example: Finch Beak Depth
Finches are seed eating birds that use their beaks to break open seeds. The depth of beak
is under polygenic control of three genes with two alleles each.
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Produce the Punnett square for the following cross.
Write only the number of dominant alleles in each cell of the Punnett square.
Use this information to create a graph demonstrating the distribution of beak
phenotypes.
Allele key:
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A= add depth
a= no depth added
B= add depth
b= no depth added
C= add depth
c= no depth added
Cross:
 Two birds which are heterozygous at all three loci
Example: Wild Columbine
The height of the columbine plant is controlled by a polygenic system. Here there are two
genes each with two alleles.
Allele key:
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M1= Tall plant
M2= Small plant
N1=Tall plant
N2=Small plant
Cross:
 Two heterozygote’s at each loci
 Produce the Punnett square for this cross