Name: David O.
Status: Other
Age: 40s
Location: N/A
Country: N/A
Date: January 2004
Question:
What comes first in living things a male or female?
Replies:
In humans, we all begin as females and early in uterine development the SRY
gene on the y chromosomes is acitivated to push the fetus towards male
charecteristics. If the sry gene is inactivated the fetus remains
female...with a y chromosome...instructing us that the chromosomal makeup is
not a certain indicater of sex.
PF
David,
The evolution of sex is a very complex topic and this forum would be hard placed
to address it. The process of exchanging chromosome information can be seen
clearly in the Monerans and Protists classification kingdoms, and the development
of males and females evolves. The bottom line i suppose is that if you have
females, you are implying that males are available. Females are certainly more
important from a functioning reproductive discussion and we see some species only
having female individuals.
There is a problem when one says that an human individual is female before the
male SRY gene turns on to develop a male. The newly conceived male embryo is carrying the XY gene
combination from fertilization and does not show the male characteristics until
further along in the development. Here is a great explanation:
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