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1. y chromosome
Male Sex Chromosome
Scientists have discovered that the Y chromosome uses a neat trick to repair its most crucial genes, a strategy that apparently helps keep it from rotting away over evolutionary time.

Instead of doubling up to protect its genetic cargo like other chromosomes, the lone Y safeguards its genes by having sex with itself, an international consortium has found. Proving perhaps that nature has a sense of humor, scientists have discovered that the Y chromosome - the one that makes a man a man - has a remarkable ability to make do-it-yourself repairs.

June 20, 2003 — The human male sex chromosome does have the ability to repair itself and may not be headed for extinction as had previously been thought, according to a surprising new study.

A 40-strong team of researchers led by David Page of the Whitehead Institute at the Massachusetts Institute of Technology, report their findings in this week's issue of the journal Nature.

As well as having a previously unknown and elaborate back-up system for self-repair, the Y chromosome also carries 78 genes.




"The Y chromosome is a hall of mirrors," said Page, whose team has for the first time identified the full genetic sequence of a Y chromosome, from an anonymous donor.

Both the male Y and female X chromosomes are thought to have originally been the same size, but after the Y took on the sex-determining role for maleness it apparently began to lose genes. At this time it also lost the ability to pair up exactly with ...
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by John Ronane Jan 31, 2004 add a video
2. y chromosome
The Y chromosome is one of the two sex chromosomes (X and Y). Only men carry the Y chromosome. The Y chromosome is male specific, passing from father to son. It is responsible for many male characteristics.
The path of evolution is usually so quirky and complex that scientists shy away from making predictions. But the future of the Y chromosome seems clear. Graves points out that, on average, three to six genes have disappeared from the Y every million years since the chromosome emerged. At that rate, the Y has only 10 million years left. It's an old chromosome, at death's door.

The death of the Y doesn't mean the death of men. Men need only look to the mole vole for comfort. Burrowing through the soil of western Asia are two species of these rodents (Ellobius tancrei and E. lutescens) that have lost all the genes from their Y chromosome--in fact, they no longer have a Y chromosome at all. In one of these species, both males and females have been left with just the unpaired X; in the other, both sexes have two X's. No one knows how mole voles ended up being the first mammals to cross over into the Y-free future. But along the way, they must have evolved new genes--on other chromosomes--that are responsible for making males. One of those genes took over the job of SRY, and the chromosome on which it resides is probably on its way to becoming the new Y.

If our species manages to survive for another 10 million years, our descendants will go on making men even after their Y chromosome vanishes. But the change may not be smooth. Graves speculates that several new systems for determining sex could emerge within the global human population. People conceived under one system mi...
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3. y chromosome
(disregard my definition above)

Chromosome which is found in males. XY = male. XX = female. Sperm can be either an X or Y chromosome. During fertilization, if the Y chromosome sperm reaches the egg, then the baby is a boy. If the X chromosome sperm reaches the egg, then the baby is a girl.
If the Y chromosome is going extinct within the next 10-50 million years, then (assuming humans will still be around) where the fuck will babies come from?! Women (XX genes) can't have babies by themselves. They need a man (XY genes). That makes no fucking sense. Third sex? XZ? WTF?
by e v i1 e1 m o Jun 22, 2004 add a video
4. y chromosome
Chromosome which is found in males. XY = male. XX = female. Sperm can be either an X or Y chromosome. During fertilization, if the Y chromosome sperm reaches the egg, then the baby is a boy. If the X chromosome sperm reaches the egg, then the baby is a boy.
If the Y chromosome is going extinct within the next 10-50 million years, then (assuming humans will still be around) where the fuck will babies come from?! Women (XX genes) can't have babies by themselves. They need a man (XY genes). That makes no fucking sense. Third sex? XZ? WTF?
by e v i1 e1 m o Mar 20, 2004 add a video
5. y chromosome
Proof that males are biologically dominant over females
The Y chromosome is dominant over the X chromosome. No matter what, a person with a Y chromosome will be male. XXY(Klinefelters) sufferers are male, albiet having TWO X chromosomes.
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