Chapter 9: Part 2 Internal Sex Ograns Flashcards
What is a Mullerian System?
it is the precursor of the internal female sex organs, which develops into the fimbriae and Fallopian tubes, the uterus, and the inner two-thirds of the vagina
What is the Wolffian system?
it is the precursor of the internal male sex organs, which develops into the epididymis, vas deferens, and seminal vesicles
what secretes hormones that determine the gender of the internal sex organs?
testes, if hormone is present… Wolffian happens. if its not, mullerian system happens.
what two hormones do the testes secrete?
anti-mullerian hormone and androgens
what does the anti mullerian hormone do?
A peptide secreted by the fetal testes that inhibits the development of the Müllerian system, which would otherwise become the female internal sex organs.
what is the defeminizing effect?
An effect of a hormone present early in development that reduces or prevents the later development of anatomical or behavioral characteristics typical of females.
what do androgens?
stimulates the development of wolffish system - A male sex steroid hormone. Testosterone is the principal mammalian androgen.
what type of effect do androgens have?
masculinizing effect?
what are two different androgens that are responsible for masculinization?
testosterone and dihydrotestosterone…. enzymes concert some testosterone into dihydrotestosterone
what is androgen insensitivity syndrome? (males)
males (XY) get testes and anti-mullerian hormones & secrete androgen BUT don’t have the receptors for them so their internal sex organs do not develop. nor does female internal sex hormones since they have the antimullierian hormone for defeminizing effect. The external genitalia are female, and at puberty the person develops a woman’s body. Of course, lacking a uterus and ovaries, the person cannot have children.
what causes the androgen insensitivity syndrome?
genetic mutation that prevents the formation of functioning androgen receptors, the gene for androgen receptors are on the X chromosome
what causes persistent mullerian duct syndrome?
two causes: either a failure to produce anti-Müllerian hormone or the absence of receptors for this hormone
what is persistent mullerian duct syndrome?
When this syndrome occurs in genetic males, androgens have their masculinizing effect but defeminization does not occur. Thus, the person is born with both sets of internal sex organs, male and female. The presence of the additional female sex organs usually interferes with normal functioning of the male sex organs. So far, I have been discussing only male sex hormones.
what are two genetic disorder that happen to males?
androgen insensitivity syndrome and and mullerian duct syndrome
what is turners syndrome?
when a person only has one X chromosome (X0, missing a second X or Y) - no Y so testes don’t develop - no ovaries since two X’s are needed - no gonads but become females with internal sex organs NO GONADS (testes or ovaries) BUT DOES HAVE FEMALE INTERNAL SEX ORGANS AND FEMALE EXTERNAL GENETALIA. also, cannot bear children since there’s no ovaries
