Human Sex Determination
Name: Jessica M.
Date: May 2004
My friend and I are arguing two different things. She
says that the baby's sex can not be determined until the seventh week of
the pregnancy that until then the baby is both sexes. However, learned
that the baby sex is determined by which chromosome of the sperm
fertilizes the egg an X or a Y. Which is true?
Both. Sort of. The baby's sex is determined at fertilization based on whether the baby
receives an X or a Y. However, you can't TELL whether the embryo is a boy or girl by
looking at it until about 7 weeks because that is when the sexual characteristics begin
Neither is true! Sex determination is extremely complex and partly a
philosophical issue. What is a person's sex if they have an inactive y
chromosome sry gene that allows for androgen sensitivity... A female,
typically sterile. Typically, maleness begins being determined to some
extent when the sry gene turns on but this is only a very reductive static
look...what happens later matters enormously. What does it mean to be a
person? Although genes hod information that helps determine the
developmental fate of a body the chromosomes or genes are not our identity,
nor is their protein products.
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Update: June 2012