Why incomplete dominance name given to blending?

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In summary, the terms "incomplete dominance" and "co-dominance" are used to describe different situations where there is a mix of dominant and recessive genes. incomplete dominance is used when one of the dominant genes produces a dose, and co-dominance is used when both genes produce a dose. The terms are helpful, but one cannot always tell the mechanism from the phenotypes of various crosses.
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Frigus
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In incomplete dominance we say that trait expressed in F₁ is mixture of parents trait and in co dominance both the traits are expressed.
Now problem is that even in co dominance their is not complete dominance of any trait so why do we call only intermediate/mosaic inheritance as incomplete dominance.
It makes sense to me if we say both of these fall in category of incomplete dominance but it is not the case as we call only mosaic inheritance as incomplete dominance.
Thanks
 
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Probably for your exam, you should learn the terms as you were taught.

See if you like this: https://www.ncbi.nlm.nih.gov/books/NBK21920/
Roughly, incomplete dominance is used when the dominant allele produces something (a "dose"), and the recessive allele produces nothing. The idea is that the "standard" dominant/recessive situation is due to haplosufficiency, and incomplete dominance is modified haplosufficiency.
Co-dominance is used when both alleles produce something.

I do think these terminological distinctions are not that helpful. I do think the understanding in terms of mechanism is important and helpful. However, I don't think one can generally tell the mechanism from the phenotypes of various crosses.

Some more viewpoints here:
https://doi.org/10.1590/S0100-84551997000400018
https://dx.doi.org/10.1371/journal.pbio.1001356
 
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atyy said:
Probably for your exam, you should learn the terms as you were taught.

See if you like this: https://www.ncbi.nlm.nih.gov/books/NBK21920/
Roughly, incomplete dominance is used when the dominant allele produces something (a "dose"), and the recessive allele produces nothing. The idea is that the "standard" dominant/recessive situation is due to haplosufficiency, and incomplete dominance is modified haplosufficiency.
Co-dominance is used when both alleles produce something.

I do think these terminological distinctions are not that helpful. I do think the understanding in terms of mechanism is important and helpful. However, I don't think one can generally tell the mechanism from the phenotypes of various crosses.

Some more viewpoints here:
https://doi.org/10.1590/S0100-84551997000400018
https://dx.doi.org/10.1371/journal.pbio.1001356
Thanks sir,
I will memorize their name and understand what's going on in the Crosses,earlier also I have been earlier told that our definitions are arbitrary and change with time and are not perfect.
🙂
 
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Related to Why incomplete dominance name given to blending?

1. Why is it called "incomplete dominance"?

The term "incomplete dominance" refers to a type of inheritance pattern where the heterozygous phenotype is a blend of the two homozygous phenotypes. This is in contrast to complete dominance, where the dominant allele completely masks the recessive allele in the heterozygous phenotype. The term "incomplete" is used because the heterozygous phenotype is not completely dominant or recessive, but rather a combination of both.

2. What is the difference between incomplete dominance and codominance?

In incomplete dominance, the heterozygous phenotype is a blend of the two homozygous phenotypes. In codominance, both alleles are expressed equally in the heterozygous phenotype. For example, in incomplete dominance, a red and white flower would produce a pink flower, whereas in codominance, a red and white flower would produce a flower with both red and white patches.

3. How is incomplete dominance different from blending inheritance?

Incomplete dominance is a type of inheritance pattern where the heterozygous phenotype is a blend of the two homozygous phenotypes. Blending inheritance, on the other hand, is a now outdated theory that suggested that the traits of the parents blend together to create the traits of the offspring. In incomplete dominance, the traits of the parents do not blend, but rather a new phenotype is created.

4. Can incomplete dominance occur in non-plant organisms?

Yes, incomplete dominance can occur in non-plant organisms. It is a common inheritance pattern in animals, such as in the coat color of horses or the color of feathers in birds. It can also occur in humans, such as in the case of sickle cell anemia, where the heterozygous genotype results in a milder form of the disease.

5. How is incomplete dominance different from polygenic inheritance?

In incomplete dominance, a single gene with two alleles is responsible for the variation in phenotype. In polygenic inheritance, multiple genes with multiple alleles contribute to the variation in phenotype. Incomplete dominance results in a blending of the two homozygous phenotypes, whereas polygenic inheritance can result in a wide range of phenotypes due to the contribution of multiple genes.

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