quantumlust Wrote:
Quote:
The explanation that we all start off as females is incorrect - a more accurate view would be that human fetuses start off with very generalized plumbing (precursors to either male or female gonadal tissue) and undifferentiated external genitalia. It is the action of the genes expressed differentially due to the heterogametic sex chromosomes that results in the developmental cascades leading to the development of the gonadal tissue, and, 12 or 13 years later, the secondary sexual characteristics.
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Good work, prof.
As for the fixation on XX males, as a result of traslocation of the SRC gene- the female counterpart to this is an XY female with androgen insensitivity syndrom. Like the professor said, this is more a matter of hormones, not sex chromosome aneuploidy. It all depends on whether this translocation included the SRC gene.
(and once you get into a discussion of mosaics...you find a whole new clusterfuck.)
In general-
there are
xx females (normal)
xy males (normal)
xxy males (Klinefelter's syndrome, "tall skinny boys who need a bra")
xo females (Turner's Syndrome: usually short with broad chest,ect)
xxx females
xyy males (NOT hyperaggressive, contrary to misleading information)
In theory there can also be XXXX females, but this arrangement tends to be weak and inviable to life.
good lord, christy, you're all over the internets, aren't you?
then there's the whole question of why heterogametic sex chromosomes at all, and how long before the human Y chromosome will go extinct (or will it - can intrachromsomal recombination in the human Y combat Muller's Ratchet)?
but shit, we're all here to talk about music . . .
np: G-Force - Why Do Men Have Nipples? (Wax Trax, 1989)
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Radcliffe Wrote:
I'm kinda like Jesus in that respect. And Allah. Jesus and Allah all rolled up into a single ball of seething bitter rage.
