In the Y chromosome in males, what is missing that one would find in an X chromosome?
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In the Y chromosome in males, what is missing that one would find in an X chromosome?
One thing is the gene for the third cone in the retina.
Birds and reptiles have four cones.
Lower mammals have two. Two were lost due to mutation and wasn't a big problem as these early mammals were nocturnal and had little need for color vision.
Higher mammals have duplicated one of the two cones and then mutated it a bit so as to get a bit wider spectrum of colors (but still not as wide as birds and reptiles who can see into the ultraviolet.)
This duplicated and mutated gene is on the X chromosome. This is why it is men who are prone to color blindness. They only have one copy of the the gene and if it is a defective version, then they're color blind.
Women have two copies and thus have a lower percentage of being color blind.
Although. I've often wondered about how X chromosome inactivation plays in to this. Only one X chromosome is active in women. The other randomly selected and inactivated...
Something to look into one of these days.
Some genes from distant generations.
Also possibly the gene for hairy ears.
My understanding [open to correction] is that:Originally Posted by Chemboy
We are all basically female (ie have an 'X' chromosome) but where a 'Y' is present this dominates (suppresses) the female 'X' If this is true then it seems that there is nothing 'missing' from the 'Y' but something extra, [maleness].
In other words it could easily be that everything in an 'X' is in a 'Y' but not everything in a 'Y' is in an 'X'.
My last biology lesson was in the early 1950's (just prior to the discovery of DNA!) - So I could be wrong.
this is not entirely true. womans that have the combination XY have a defect in the toher chromosones that makes them unable to respond to testosterone and by that in the featus stage turns into a woman. But at puberty nothing happens since the X chromosones need a partner to be activated.We are all basically female (ie have an 'X' chromosome) but where a 'Y' is present this dominates (suppresses) the female 'X' If this is true then it seems that there is nothing 'missing' from the 'Y' but something extra, [maleness].
And genes have been removed from the Y to prevent genes to be transfered from X to Y and causing trouble.
The fact that I said 'basically' should indicate that what I said was generally but not necessarily entirely true.
I also indicated that my knowledge may be a little out of date, If you could cite a credible source I will be happy to amend my opinion.
As I understand it the common definition of a male is one with an XY whereas a woman has XX Therefore (if I am correct) you cannot say "A woman with XY"
i can since it was a she physical. had a vagina and a whom. but no breasts or anything else since she had,even at the age of 20, neveg gone throu puberty. and it was becuase the missing X
dont remember the dokumentarys name but it was on discoveryIf you could cite a credible source I will be happy to amend my opinion.
As I said my definition of male is 'possessing the xy' - female is 'xx'.Originally Posted by Zelos
That is the definitition I was given at school - good enough for me.
You might like to swot up on the exact difference between X and Y - 'Y' is a shortened version of 'X' The 'X' is the FULL SET. The 'Y' is the reduced set, This is why females are superior, they have a FULL SETof the genetic code, US guys are a few genes short of a wardrobe!.
http://www.bbc.co.uk/scotland/educat...tance_12.shtml
Females have two copies of the fully formed chromosome which is referred to as the "X" chromosome, so we say that females are XX. This means that mothers always pass an X chromosome to their offspring whether they are girls or boys. Males, however have one copy of a shortened version, with many genes missing. This is referred to as the "Y" chromosome, ao we say that males are XY. This means that the sperm can carry an X chromosome or a Y chromosome, and exactly half of all the sperm produced carry the X and so produce female offspring, whilst the other half pass on the Y chromosome and produce males. Just remember that "the guy gets the Y"
Now I have offered rational argument, and reputable sources of reference, you have pointed to a documentary but cannot recall what it was called or any other details, and have been unable to find any evidence to support your wild claims.
2 years ago when I was in highschool my biology teacher told me that there is no vital information contained in any gene of the Y chromossome. That it only had information related to behaviour..
nice try, not working. we have all the genes we need. and by having less genes and still working makes us better if any is better. the less crap you can walk with that isn´t needed the better. So girls are acctualy by your logic inferior since they have alot they dont need.You might like to swot up on the exact difference between X and Y - 'Y' is a shortened version of 'X' The 'X' is the FULL SET. The 'Y' is the reduced set, This is why females are superior, they have a FULL SETof the genetic code,
http://en.wikipedia.org/wiki/XX_male_syndromeNow I have offered rational argument, and reputable sources of reference, you have pointed to a documentary but cannot recall what it was called or any other details, and have been unable to find any evidence to support your wild claims.
http://en.wikipedia.org/wiki/XY_sex-...ination_system
there it is, saying taht females can have XY and males can have XX
Originally Posted by Zelos
Try this one again, it now has your name in it!
http://en.wikipedia.org/wiki/XX_male_syndrome
Ah now I see!
Wikipaedia is NOT an authoratitive source, it is compiled by the public FOR the public. Anybody can edit it!!
billco, youre only saying that since i have proven you wrong.
Sure anyone can edit, but the correct one will remain there since incorrect changes will be deleted and people doing it will be banned.
Billco take a time machine and go back to the 19th centry. You are out-of-date now.
This kind of errors are called biological errors. Imagen anykind of chromosone disorder and you have it somewhere in human history. XXX, XXY,XYY,YY and so on. they have all existed at sometime, thou the YY won´t survive since vital genes are missing
Billco expire date: 200585
In the following link you will the different chromosomes in humans by klicking on them you’ll see which genes are located on the different chromosomes if you want you can compare X and Y
http://www.ncbi.nlm.nih.gov/mapview/map_search.cgi
Is there any need for that sort of talk? do you get a kick out of kicking pensioners? I think you ought to be ashamed of yourself, If I had your address I'd send around a set of my Killer false teeth!Originally Posted by Zelos
genotypes XXX, XXY, XYY, etc. are caused by nondisjunction of chromosomes during meiosis.
Some people like to say that there's a high proportion of XYY's in jail because they have a double Y and are hence very aggressive and troublesome.
But it's not true.
From my understanding of XY chromosomes it is wrong to think of males as 'deficient' for some genes. This is a misunderstanding, promoted by feminism. In fact its the other way round, males have a few Y-specific genes that females completely lack.
The Y-chromosome is not fragment of the X-chromosome. In fact only 5% of the Y-chromosome corresponds to X-chromosome sequence, the rest is unique.
Since we also have an X-chromosome we have ALL the genes that females do.
It is only true to say that females have two alleles of many genes for which males only have a single copy.
maybe, but as i have seen now it seems like you are out of date with more than opnionsIs there any need for that sort of talk? do you get a kick out of kicking pensioners? I think you ought to be ashamed of yourself, If I had your address I'd send around a set of my Killer false teeth!
but as you can see XX/XY doesn´t make a girl/guy
Always ready to learn in the light of new experience, you know me, adapt and survive!Originally Posted by Zelos
Now where's matron with my bloody pills!
maybe where you put your glasses![]()
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