ATAR Notes: Forum
HSC Stuff => HSC Science Stuff => HSC Subjects + Help => HSC Biology => Topic started by: Nialllovespie on July 30, 2017, 12:21:36 pm
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Hey!
Is anyone able to explain the difference between codominance and Incomplete dominance?
I'm so confused!!
Thanks!!
Nia :)
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Nice question!
Codominance refers to when two alleles are dominantly expressed. So, both alleles will be fully expressed.
In humans, codominance occurs with ABO blood groups. Since the A and B alleles are both dominant, a third genotype may be expressed, namely AB. This is because the dominance of both A and B will BOTH be completely expressed.
Incomplete dominance is kind of like its polar opposite. Neither of the two alleles are fully expressed, so the third genotype will be a blend of the two. For example, the snapdragon is homozygous for red and white flowers. When the red and white are crossed, neither are fully expressed resulting in a blend of the two.
Hopefully, this helps!