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Name: Jessica M.
Status: Student
Age: 20s
Location: N/A
Country: N/A
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 to develop.


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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