- Uterus (single)—superior to the urinary bladder
and between the two ovaries (see Fig. 20–5).
Myometrium is the smooth muscle layer that con-
tracts for delivery (see Fig. 20–6). Endometrium is
the lining which may become the placenta; basilar
layer is permanent; functional layer is lost in men-
struation and regenerated. Parts: upper fundus,
central body, and lower cervix. - Vagina (single)—extends from the cervix to the
vaginal orifice (see Figs. 20–5 and 20–6). Receives
sperm during intercourse; serves as exit for men-
strual blood and as the birth canal during delivery.
Normal flora provide an acidic pH that inhibits the
growth of pathogens. - External genitals (see Figs. 20–5 and 20–7)—also
called the vulva. The clitoris is a small mass of erec-
tile tissue that responds to sexual stimulation; labia
majora and minora are paired folds of skin that
enclose the vestibule and cover the urethral and
vaginal openings; Bartholin’s glands open into the
vaginal orifice and secrete mucus.
Mammary Glands—anterior to the pectoralis
major muscles, surrounded by adipose tissue
(see Fig. 20–8)- Alveolar glands produce milk; lactiferous ducts
converge at the nipple. - Hormonal regulation—see Table 20–2.
The Menstrual Cycle—average is 28 days;
includes the hormones FSH, LH, estrogen,
and progesterone, and changes in the
ovaries and endometrium (see Fig. 20–9 and
Table 20–3)- Menstrual phase—loss of the endometrium.
- Follicular phase—several ovarian follicles develop;
ovulation is the rupture of a mature follicle; blood
vessels grow in the endometrium. - Luteal phase—the ruptured follicle becomes the
corpus luteum; the endometrium continues to
develop. - If fertilization does not occur, decreased proges-
terone results in the loss of the endometrium in
menstruation.
472 The Reproductive Systems
REVIEW QUESTIONS
- Describe spermatogenesis and oogenesis in terms
of site, number of functional cells produced by each
cell that undergoes meiosis, and timing of the
process. (p. 456) - Describe the functions of FSH, LH, inhibin, and
testosterone in spermatogenesis. Describe the func-
tions of FSH and estrogen in oogenesis. (p. 456) - Describe the locations of the testes and epi-
didymides, and explain their functions. (pp. 457,
459, 461) - Name all the ducts, in order, that sperm travel
through from the testes to the urethra. (p. 461) - Name the male reproductive glands, and state how
each contributes to the formation of semen. (pp.
461–462) - Explain how the structure of cavernous tissue per-
mits erection of the penis. Name the structures that
bring about ejaculation. (p. 462) - State the function of each part of a sperm cell: head,
middle piece, flagellum, and acrosome. (p. 459) - Describe the location of the ovaries, and name the
hormones produced by the ovaries. (pp. 462–464)
9. Explain how an ovum or zygote is kept moving
through the fallopian tube. (pp. 464–465) - Describe the function of myometrium, basilar
layer of the endometrium, and functional layer of
the endometrium. Name the hormones necessary
for growth of the endometrium. (p. 465) - State the functions of the vagina, labia majora and
minora, and Bartholin’s glands. (p. 466) - Name the parts of the mammary glands, and state
the function of each. (p. 467) - Name the hormone that has each of these effects
on the mammary glands: (p. 468)
a. Causes release of milk
b. Promotes growth of the ducts
c. Promotes growth of the secretory cells
d. Stimulates milk production - Name the phase of the menstrual cycle in which
each of these actions takes place: (p. 468)
a. Rupture of a mature follicle
b. Loss of the endometrium
c. Final development of the endometrium
d. Development of the corpus luteum
e. Development of several ovarian follicles