Posted by: GuN
Posted by: Player3Th0mas1
Yes you are, admit it!
Partly
XY - XX Proof
Prove me wrong
Alright, I'll give it a shot.
The Y chromosome contributes very little to a human being, even to the point where it is much smaller than the X chromosome and has many many less number of genes. In fact, most genetic disorders are caused by a defect in the X chromosome, not the Y.
But what the Y chromsome does contribute is the SRY gene, which stimulates testosterone production and the formation of the testes. Basically, if a fetus has a Y chromosome, the SRY gene will stimulate the production of male s exual features and the male reproductive organs. This means that the male fetus produces DIFFERENT hormones and the cell division creates COMPLETELY different reproductive organs and gametes (i.e. female gametes, the eggs, are structurally speaking NOTHING like sperm cells and the two also perform cell division two completely different process--oogenesis and the creation of Barr/polar bodies and eggs is nothing like spermatogeneis where spermatogonia perform either mitosis or meiosis to make more spermatogonia or spermatocytes--spermatocytes are immature gametes that later, in the epididymis mature into sperm cells).
So, SRY basically creates a human being that is VERY different from a female, with many many different hormone systems, VERY different reproductive organs physical features and methods of cell division for the respective gametes. This is why people with XXY are still male-the SRY gene still creates production of enough testosterone and testes to create male g enetalia.
In the absence of a Y chromosome, be it just one X (turner syndrome) or a normal XX, there is no SRY, so different hormones get activates and a female is the result with female characteristics and reproductive organs.
In both cases, the absence or presence of SRY decides what happens to the fetus in terms of development (the s e x hormones testosterone and estrogen also contribute to physical features, such as presence of body hair, height, distribution of body fat, muscle development, etc). I.E.-SRY leads to the creation of a completely different being than a female, different hormones, different gametes, entirely different reproductive system.
So, as you can see, although both males and females, albeit sharing an X (XX vs XY) are ultimately different in the way that s e x steroids, testosterone, estrogen and progesterone, shape their body. Males NEED an X chromosome because the Y chromosome literally has jack -blam!- on it, aside from SRY. The X chromosome codes for the creation of the rest of the body systems, from the circulatory system to the brain to the skin (which is why, as I mentioned before, most genetic diseases are transmitted through the X chromosome, because it does most of the construction of the baby while it's still in the uterus developing).
So, basically, saying that boys are part girls because both have an X chromosome is pretty stupid. That being said, it does mean we are both human, because most of the creation of a human body is attributed to the X chromosome.
Did. Read. You are the only one who is right, some other guy too, but he didnt take the time to type this much.