Last Week in….
We discussed the different forms of Reproduction
We discussed the costs/benefits of each form
This week we’ll discuss sexual
differentiation - how sexually reproducing organisms develop
into separate sexes. Specifically, as it applies to us humans
SO…How Do We Get From…
(essentially a clump
(fully developed adult female)
(fully developed adult male)
In other words, How do our bodies know if we are meant to use the little boys’ room or the little girls’ room?
It’s the factor!
The Y chromosome contains a gene known as the SRY (sex determining region on the Y chromosome) gene.
This gene is responsible for the development of testes
But what about the factor?
Unless testes develop, this area will naturally develop into the female reproductive system
In other words, we are all female by default
BUT…how does this happen??
When testes form they release 2 hormones - testosterone & MIS (mullerian inhibiting substance)
The testosterone causes the male reproductive system to develop
MIS causes the ducts of the female system to degenerate
of mature male
leads to the
Female reproductive organs