1. Right side: Exposed to T and MIH, so Wolffian duct develops into vas deferens and Mullerian disintegrates. Left side: Exposed to T (via blood) but not MIH (because paracrine secretion), so Wolffian duct develops into vas deferens AND Mullerian duct develops into oviducts/uterus.

2. A. Androgen insensitivity syndrome: testis, Mullerian and Wolffian ducts both disintegrate, female genitals, produce T.
B. Lack of SRY region of Y chromosome: ovary, Wolffian disintegrates, Mullerian develops into oviduct/uterus, female genitals, produce E/P.

3. Aromatase converts T to E, so should be more prevalent in ovaries than in testes, and ovaries should produce more estrogen and less testosterone than testes (and this is supported by the results in the graph). The middle bar of each graph shows what happens when ovaries are treated with AMH: They start to act like testes, secreting lots of T, little E, and apparently having this effect because they inhibit activity of the aromatase. Remember, an indifferent gonad can become either an ovary (with aromatase) or a testes (without aromatase), depending on the presence of SRY. Scientists have suggested that SRY might make the gonad male-like by switching off the aromatase gene. The results support the idea that AMH functions to ensure that the testes develops in the male direction, becoming a testosterone-secreting gland, rather than the default estrogen-secreting gland.

4. The home pregnancy test measures hCG, which normally has the effect of maintaining the corpus luteum, just like LH does. In fact, its structure is very similar to that of LH. High LH can react with the antibodies used in the preg test, so she'll give a positive response if she has high LH. This can occur naturally just before ovulation, of course. In addition, it will occur when negative feedback from the ovaries is removed. This occurs naturally at menopause, when the decreased secretion of ovarian hormones leads to high levels of gonadotropic hormones being measured in the blood.

6. Here's the answer to part B first:. CAH: genitals: male-like, breasts: female. AIS: both are female. Guevo and XX w/SRY: male genitals & no breast development
A. CAH seems most likely here, since genitals are male-like, and breasts do develop at puberty in response to E. But, in fact, the statues themselves have genitals that are unambiguously male. It could be that they were based on something like CAH, but the traits were exaggerated, or that they were based on Klinefelter's syndrome, in which female-like breasts often develop. It is also, of course, possible that they resulted from the Greeks' imagination, and we'd be mistaken to assume that such people existed, just like archaeologists 2000 years hence would be mistaken to view objects from our times as evidence that our generation coexisted with a species of purple dinosaur.

8. Vinclozolin may inhibit 5-alpha reductase, the enzyme responsible for conversion of T to DHT, so that external genitals do not get enough stimulation for complete masculine development. Alternatively, vinclozolin may be blocking the receptors for DHT, so that even though the hormone is present, it cannot affect the tissue.

9. Significant progesterone is secreted only from the corpus luteum, not the follicle, so you'd expect to see progesterone only in the second half of the cycle, and only if ovulation has occurred. So you'd want to assay in the middle of the luteal phase, but this is hard to pinpoint, since it depends on cycle length. Best estimate would be to start counting from day 1 of menstruation, and then assay 21-22 days later. If the cycle's exactly 28 days, you'd hit the peak of P secretion. If the cycle is shorter or longer than 28 days, you'd be at the beginning or end of the luteal phase, so would still be likely to find P. NOTE: Measuring LH would also indicate the likelihood that ovulation will occur in this cycle, but because the LH peak is very brief (1 day), you're likely to miss this day, considering the lack of equipment available to you. Same argument holds for FSH and GnRH. The latter is also not a good choice, because levels in the peripheral blood are so low. E is high both before AND after ovulation, so if you measure just one point, you won't know which time you're measuring, and whether ovulation occurred.

10. B. Androgens are required for masculinization of external genitals, which usually depends on conversion of testosterone to DHT. In this case, the female produces androstenedione, which crosses the placenta to the fetus. Since it can be converted to other androgens, it's able to masculinize the genitals of the female. (The female actually gives birth through the relatively small vaginal opening in this penis-like organ.)

11. Since LH is normal, the hypothalamus and GnRH must be okay. Problem is either that the Sertoli cells can't respond to FSH (eg, no receptors), or they don't produce enough inhibin. (In fact, the latter has been shown to occur in some such men.)

12. A. Anabolic steroid acts like T to inhibit GnRH, so less gonadotropins, less stimulation of testes, which atrophy.
B. The androgens can be aromatized to estrogens, which promotes breast growth.

13.  Expt 2 and 4 show that a sudden lowering of progesterone can bring on menstruation, whether or not estrogen is present.  Expt 1 and 3 show that a sudden lowering of E can bring on menstruation, but only if progesterone is absent.  In an anovulatory cycle, there is no progesterone since no corpus luteum was formed, and so the menstruation that occurs must be due to the sudden decrease in E secretion, which would come in this case from the follicle, not the corpus luteum.

14. A.  b>a     B. a=b      C. b>a                  15. b.  (or you could say g. ...  requires just SRY)

16. a         17. b. c.               18. myometrium          19. inhibin          20. Prostaglandins       

21. A. Sometimes.  Could be a CAH female.          B. Sometimes.  Could be from adrenal cortex, or from peripheral fat cells.