Chapter 16

What feature of the reproductive system makes it unique from each of the other body systems? (Hint: Consider the survival of an individual versus a species.)

Of what functional significance is the scrotal location of the testes?

Occasionally, testicular tumors composed of interstitial cells of Leydig may secrete up to 100 times the normal amount of testosterone. When such a tumor develops in young animals, they grow up much shorter than their genetic potential. Explain why. What other symptoms would be present?

The hypothalamus releases \(\mathrm{GnRH}\) in pulsatile bursts once every two to three hours, with no secretion occurring in between. The blood concentration of GnRH depends on the frequency of these bursts of secretion. A promising line of research for a new method of contraception involves administration of GnRH-like drugs. In what way could such drugs act as contraceptives when GnRH is the hypothalamic hormone that triggers the chain of events leading to ovulation? (Hint: The anterior pituitary is "programmed" to respond only to the normal pulsatile pattern of GnRH.)

Describe the events of the follicular and luteal phases of the ovarian cycle. Correlate the phases of the uterine cycle with those of the ovarian cycle.