Dominance

Discussion of everything related to the Theory of Evolution.

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pankaaj
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Dominance

Post by pankaaj » Mon Mar 19, 2007 11:15 am

Has dominance evolved? I mean..wat is the exact concept of Dominance/recessive allel?
Take it with a pintch of salt!

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Post by Darby » Mon Mar 19, 2007 2:58 pm

In some ways, you're asking the wrong question.

Recessiveness is the target here, since recessive alleles often code for proteins that don't work properly, if at all.

For instance, Mendel's original tall-short alleles were a "normal" growth hormone allele, and an allele that produced a non-functioning version. With one OR two alleles present, growth hormone is produced and the plants grew to normal height; with two recessive alleles, no working growth hormone was made and the plants were very short.

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Poison
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Post by Poison » Mon Mar 19, 2007 8:09 pm

We can not say "evolve" for dominance. Alleles are formed by mutations.
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pankaaj
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Post by pankaaj » Sat Mar 31, 2007 9:54 am

Its like that only ...only thing is that we dont call it evolution/adaptation..we call it dominance!
Accordin to Hardy Weinberg equalibrium the removal of allele needs a lot of time and it is impossible in Natural Populations hence onlt recessive gets survived ( in the form of Heterozygots also)...
Take it with a pintch of salt!

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Post by Darby » Sat Mar 31, 2007 5:17 pm

You've got a lot of concepts very confused.

Hardy-Weinberg doesn't say what you think it does - just the opposite, since the conditions for the continuation / elimination for alleles are mostly not features actually found in Nature.

Also, dominance just addresses the likelihood of an allele being expressed observably - it's what that allele's protein does that's important.

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Post by Locus » Sun Apr 01, 2007 6:29 pm

Why not? It is simply hard to observe and takes relative much time, and depend on the selection pressure.
Evolution will arrange everything

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