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Chapter 17
24. State the sources of estrogen and progesterone during different
stages of pregnancy. What is the dominant estrogen of
pregnancy, and how is it produced?
25. What is the state of gonadotropin secretion during pregnancy,
and what is the cause?
26. What anatomical feature permits coordinated contractions of
the myometrium?
27. Describe the mechanisms and messengers that contribute to
parturition.
28. List the effects of prostaglandins on the female reproductive
system.
29. Describe the development of the breasts after puberty and
during pregnancy, and list the major hormones responsible.
30. Describe the effects of estrogen on the secretion and actions of
prolactin during pregnancy.
31. Diagram the suckling refl ex for prolactin release.
32. Diagram the milk ejection refl ex.
33. List two main types of amenorrhea and give examples of each.
34. What is the state of estrogen and gonadotropin secretion
before puberty and after menopause?
35. List the hormonal and anatomical changes that occur after
menopause.
36. Why would glucocorticoids given to a pregnant woman help to
treat her fetus with congenital adrenal hyperplasia?
Chapter 17 Test Questions
(Answers appear in Appendix A.)
1. Development of normal female internal and external genitalia
requires
a. Müllerian-inhibiting substance.
b. expression of the
SRY
gene.
c. insensitivity to circulating testosterone.
d. complete absence of testosterone.
e. absence of a Y chromosome.
2. Which is
not
characteristic of a normal postpubertal male?
a. Inhibin from the Sertoli cells decreases FSH secretion.
b. Testosterone has paracrine effects on the Sertoli cells.
c. Testosterone stimulates GnRH from the hypothalamus.
d. Testosterone inhibits LH secretion.
e. GnRH from the hypothalamus is released in pulses.
Matching Questions (3–7)
Use each answer only once.
a. Day 1 of menstrual cycle
b. Day 7 of menstrual cycle
c. Day 13 of menstrual cycle
d. Day 23 of menstrual cycle
e. Day 26 of menstrual cycle
3. Progesterone from the corpus luteum peaks.
4. Estrogen positive feedback is peaking.
5. One follicle becomes dominant.
6. Estrogen and progesterone are both decreasing.
7. Increase in FSH stimulates antral follicles to begin to secrete
estrogen.
8. The Leydig cell is primarily characterized by
a. aromatization of testosterone.
b. secretion of inhibin.
c. secretion of testosterone.
d. expression of receptors only to FSH.
e. transformation into the corpus luteum.
9. During the third trimester of pregnancy, the placenta is
not
the
primary source of which hormone in maternal blood?
a. estrogen
d. inhibin
b. prolactin
e. hCG
c. progesterone
10. Menopause is characterized primarily by
a. primary ovarian failure.
b. loss of estrogen secretion from the ovary due to a decrease in
LH.
c. loss of estrogen secretion from the ovary due to a decrease in
FSH.
d. a decrease in FSH and LH due to increased inhibin.
e. a decrease in FSH and LH due to a decrease in GnRH
pulses.
Chapter 17 Quantitative and Thought Questions
(Answers appear in Appendix A.)
1. What symptom will be common to a person whose Leydig cells
have been destroyed and to a person whose Sertoli cells have
been destroyed? What symptom will not be common?
2. A male athlete taking large amounts of an androgenic steroid
becomes sterile (unable to produce sperm capable of causing
fertilization). Explain.
3. A man who is sterile is found to have the following: no evidence
of demasculinization, an increased blood concentration of FSH,
and a normal plasma concentration of LH. What is the most
likely basis of his sterility?
4. If you were a scientist trying to develop a male contraceptive
acting on the anterior pituitary, would you try to block the
secretion of FSH or LH? Explain the reason for your choice.
5. A 30-year-old man has very small muscles, a sparse beard, and a
high-pitched voice. His plasma concentration of LH is elevated.
Explain the likely cause of all these fi ndings.
6. There are disorders of the adrenal cortex in which excessive
amounts of androgens are produced. If this occurs in a woman,
what will happen to her menstrual cycles?
7. Women with inadequate secretion of GnRH are often
treated for their sterility with drugs that mimic the action of
this hormone. Can you suggest a possible reason that such
treatment is often associated with multiple births?
8. Which of the following would be a signal that ovulation is soon
to occur: the cervical mucus becoming thick and sticky, an
increase in body temperature, or a marked rise in plasma LH?
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