Not all alleles are dominant and recessive like the ones
Mendel studied in his pea plants. Some alleles are equally strong
and neither are masked by the other. When both alleles are present,
they are both expressed in the phenotype. The hybrid is a blend of
both alleles. Alleles which are equally strong are
said to be "incomplete dominant" alleles. An
example of this is found in carnations. When purebred white carnations
are crossed with purebred red carnations, the result is a pink carnation.
Incomplete dominant alleles are represented by different capitalized
letters.
Codominance, is a situation in which both alleles
are equally stong and both alleles are visible in the hybrid genotype.
An example of codominance is found in chickens. When white chickens
are crossed with black chickens, the result is not a grey chicken, but
a chicken with both black and white feathers. When expressing incomplete
alleles, both alleles are written as superscipt
capital letters placed above the letter "i".
Based on what you've learned, how would you express the
genotype of the following incomplete dominant genes?
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