# DNA and genetics?



## mistergreen (Mar 3, 2007)

Can somebody explain this if you know?

ok...
When an egg and a sperm swap chunks of their DNA to make a new DNA (child), How and why are there recessive and dominate traits?

This means that the child gets both the mom's & the dad's traits not one or the other?


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## MartialTheory (Dec 20, 2007)

well without putting all the details basically its like this. both parents give half their chromosomes to create one complete chromosome. 

now which chromosomes from which parents are random. they only get the complementry chromosome to whichever is given. 

since its random, they can have a number of combinations. ressive traits are when they need 2 ressive genes for that trait to appear. dominant only requires one gene. within those chromosomes contains upon thousands and thousands of genes. 

so then the child is randomly giving what the parents have. now if both parents are recessive for a certain trait, then the child will only have the ressive. the same if both parents are double dominate. however if both parents or one parent has a mixed gene where they have one dominate and one ressive, the outcome is changed. in the case of both parents having both dominate and recessive genes, then 3/4 of the childeren will be dominate where 1/4 will be recessive.


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## mistergreen (Mar 3, 2007)

thanks... I here found the answer too.
http://en.wikipedia.org/wiki/Ploidy
We do get 2 sets of chromosomes from the parents.

and here
http://en.wikipedia.org/wiki/Dominance_relationship


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## mistergreen (Mar 3, 2007)

I'm working out an inheritance algorithm and I'm going to cheat and just have my creatures be mono-ploid... I guess being a diploid give you more chances to survive but also complicates things for me.


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## MartialTheory (Dec 20, 2007)

inheritance algorithm? u mean like a virtual thing?

There are some things that are monoploidy but those are mainly bacteria in terms of a genetic ring. i forget the term for the moment. But most things that undergo monoploidy do so in certain stages of life. 

so maybe u may need to add that detail to it. and don't worry, its not that hard. it only gets hard when u work with more than one gene locus at a time. when u do something like a dihiybrid cross, its gets complicated. and it gets much much more as u go on.


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## mistergreen (Mar 3, 2007)

MartialTheory said:


> inheritance algorithm? u mean like a virtual thing?


yeah, I'll post it when I'm done...
You get which insect you'd like to breed and then the children as well.
You get to play with evolution.

The dominance & recessive traits thing was too complicated to work out so a monopolidy is a simpler model.


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## zach987 (Sep 13, 2005)

Haploid is a better term
Look up Utah Genetics


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## MartialTheory (Dec 20, 2007)

now your just arguing semantics. but since we are on the topic, usally when they say haploid, it is a term given when the paired chromosomes becomes unpaired such as in meoisis when createing a gamate.

monoploidy is a term for the adaptation where the organisims never had a stage where they have paired chromosomes.

both terms can be looked up, http://en.wiktionary.org/wiki/monoploid


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## mistergreen (Mar 3, 2007)

zach987 said:


> Haploid is a better term
> Look up Utah Genetics


cool link though.
thanks.

In my research, speaking of biploids, correct me if I'm wrong, how a trait becomes dominate over another is because the recessive trait is defective. For instance, blue eyes trait is defective (a mutation with no positive benefit) when compared to brown eyes.

This leads to a philosophic conclusion. There was a 'perfect' person in the beginning.


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## addo (Apr 25, 2007)

mistergreen said:


> cool link though.
> thanks.
> 
> In my research, speaking of biploids, correct me if I'm wrong, how a trait becomes dominate over another is because the recessive trait is defective. For instance, blue eyes trait is defective (a mutation with no positive benefit) when compared to brown eyes.
> ...


Its a recessive trait because the gene that normally does something it doesnt work, for example in blue eyes, the gene that is responsible for producing brown pigment in the eyes is broken. When you only get it from one parent the functional gene is still producing enough pigment to give you brown eyes, and that's why you need it from both parents to get blue eyes.

I don't get your philosophic conclusion, for example blue eyes has no positive benefit over brown, but it has no negative effects ether. Both work just fine so how is one perfect?

I personally think people should stop using "survival of the fittest" when they talk about evolution, and just say if your genes work well enough to pass themselves on then they work. or something like that .


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## mistergreen (Mar 3, 2007)

addo said:


> I don't get your philosophic conclusion, for example blue eyes has no positive benefit over brown, but it has no negative effects ether. Both work just fine so how is one perfect?


what i'm saying is in the beginning of **** Sapiens perhaps there was a man or woman with all the dominant traits, "perfect"... No recessive traits.. We all have some sort of recessive traits in us just because of time, mutations and intermixing.


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## addo (Apr 25, 2007)

mistergreen said:


> what i'm saying is in the beginning of **** Sapiens perhaps there was a man or woman with all the dominant traits, "perfect"... No recessive traits.. We all have some sort of recessive traits in us just because of time, mutations and intermixing.


Well in that case there's probably people with no recessive genes around today to, as well as back then. Its not like a **** Heidelbergensis woman gave birth one day and that was the first **** Sapiens Sapiens, there was an gradual change and there was recessive genes back then just as there is now. Some of those genes has disappeared from our genome and some new ones has appeared.

Although I did miss understand you when i first red your post. I thought you thought there was some sort of superhuman in the beginning.


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## mistergreen (Mar 3, 2007)

yeah, if you think brown eyes mean you're superhuman, then yeah, you misunderstood.

And I doubt there is anybody out there with all dominant traits.
That's why i said it was a philosophical conclusion. You're taking this too seriously.


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## addo (Apr 25, 2007)

mistergreen said:


> yeah, if you think brown eyes mean you're superhuman, then yeah, you misunderstood.


No I thought that's what you meant when you wrote -"There was a 'perfect' person in the beginning"

So that's why I wrote -"for example blue eyes has no positive benefit over brown, but it has no negative effects ether. Both work just fine so how is one perfect?" :bathbaby:


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