PSIO202 Exam 4 - Female Repro

Question 1

What are the main parts of the female reproductive tract, and their basic function?

Answer 1

vagina - sperm deposition
cervix - selective barrier
uterus - implantation, development, and contraction
oviduct - transport, site of fertilization
fimbriae - collect ovum
ovary - ovum and hormone production

Question 2

What are the 5 barriers to fertilization?

Answer 2

acidic vagina
cervical mucus
cervical WBCs
1 egg (misdirection cues)
sperm capacitation failure

Question 3

What is the typical amount of semen/sperm released?

Answer 3

2.5 mL of semen containing 100 million sperm

Question 4

How many oocytes are present at birth? How many at puberty? How many mature and ovulate over a lifetime?

Answer 4

200,000 to 2 million at birth
40,000 at puberty
400 mature and ovulate

Question 5

Each month, several follicles containing a ——– ——– begin maturing, but only one ——- ——— fully matures and is ovulated.

Answer 5

primary oocytes
secondary oocyte

Question 6

If a secondary oocyte is fertilized, it becomes a ——— which is (diploid/haploid).

Answer 6

zygote, diploid

Question 7

Describe oogenesis.

Answer 7

Oogonium goes through mitosis into a primary oocyte.
Meiosis 1 begins before birth and pauses at prophase I.

Meiosis 1 completes in 1 oocytes each month, this produces a secondary oocyte that is ovulated and starts Meiosis 2. Meiosis 2 completes if the oocyte is fertilized, which would produce a zygote.

Question 8

Each follicle consists of…

Answer 8

an oocyte and follicular cells

Question 9

What is the progression of maturing ovarian follicles?

Answer 9

primordial, primary, secondary, tertiary, and graafian/mature

Question 10

What are the defining features of each type of ovarian follicle?

Answer 10

primordial - single layer of follicular cells
primary - single layer of granulosa cells
secondary/tertiary - few layers of granulosa and theca cells
graafian/mature - layers of granulosa/theca cells and a large antrum

Question 11

What is the functional unit of an ovary, and the primary endocrine tissue that secretes estradiol during the first half of the ovarian cycle?

Answer 11

the follicle

Question 12

What are the phases of the ovarian cycle?

Answer 12

follicular (development), ovulation (release of egg), and luteal (degeneration)

Question 13

What occurs in the follicular phase of the ovarian cycle?

Answer 13

primary oocyte suspended in the first meiotic division at birth
cohort of follicles grows each month (granulosa and theca cells proliferate)
in one follicle FSH and LH stimulate the antrum to form and grow
mature follicle produces estradiol (requiring LH and FSH)

Question 14

How is estradiol produced?

Answer 14

theca cells:
- LH stimlates cholesterol —> progesterone, which turns into androstenedione

granulosa cells:
- androstenedione from the theca cells turns into testosterone
- FSH stimulates testosterone —> estradiol

Question 15

What is the basic, summarized role of the theca and granulosa cells in estradiol production?

Answer 15

theca cells use LH to make the precursors

granulosa cells use FSH to turn those precursors into estradiol

Question 16

What occurs in the ovulation phase of the ovarian cycle?

Answer 16

wall of the follicle is broken down by proteases, collagenases, and prostaglandins
the follicle ruptures, releasing the ovum into the abdominal cavity

Question 17

What occurs in the luteal phase of the ovarian cycle?

Answer 17

influenced by LH, follicle wall transforms into the corpus luteum
corpus luteum produces progesterone and estrogen (and some relaxin and inhibin)
if there is no fertilization after 2 weeks, luteolysis breaks down the corpus luteum

Question 18

Describe the layers of uterus histology.

Answer 18

endometrium: stratum functionalis and stratum basalis
myometrium: smooth muscle, 3 layers
perimetrium: visceral peritoneum

Question 19

What are the three phases of the uterine cycle?

Answer 19

menses (degeneration), proliferation (growth), and secretory (secretions)

Question 20

Describe the time course of the uterine cycle.

Answer 20

Day 1 is the first day of menses and lasts about 5 days
The proliferative phase lasts 8-10 days starting at end of menses and lasting until ovulation (from about day 6-day 14)
The secretory phase begins after ovulation and continues to day 28 (the day the next menses starts)

Question 21

How do hormones regulate the uterine cycle? What is the difference between when fertilization occurs and when it doesn’t?

Answer 21

without fertilization: corpus luteum degenerates after 2 weeks and the stratum functionalist is lost in menses

with fertilization, the embryo with starts to produce hCG which halts the degeneration of the corpus luteum, and supports the pregnancy. After 3-4 months the placenta takes over hormone production.

Question 22

What are the phases of the female reproductive cycle?

Answer 22

menstrual, preovulatory, ovulation, and postovulatory

Question 23

What is the menstrual phase, and what occurs during it?

Answer 23

lasts about 5 days, beginning marks day 1 of the cycle
ovary: ~20 follicles that began to develop now begin to secrete estrogen, and fluid from the granulosa cells fills the antrum
uterus: declining progesterone cases spiral arteries to constrict and glandular tissue degenerates, stratum functionalis layer sloughs off with 50-150 mL of blood

Question 24

What is the preovulatory phase and what occurs during it?

Answer 24

Day 6-13, most variable timeline

ovary: follicles secrete estrogen and inhibin slows the secretion of FSH, dominant follicle emerges by day 6, by day 14 the Graafian follicle has enlarged and bulges at the surface, and increased estrogen levels trigger the secretion of LH

uterus: increased estrogen levels repair and thicken the stratum functionalis to 4-10 mm in thickness

Question 25

How is it that the effect of estrogen is dependent on concentration?

Answer 25

moderate concentration: estrogen inhibit release of GnRH
high concentration: estrogen stimulates release GnRH

Question 26

How is ovulation triggered (hormonally)?

Answer 26

mature follicles secrete estrogens which stimulate release of GnRH and LH
GnRH stimulates release of FSH and LH
LH surge triggers ovulation

Question 27

What is the postovulatory phase and what occurs during it?

Answer 27

about 14 days
ovary: no fertilization - corpus albicans forms and secretions of GnRH, FSH, and LH rise as hormones drop
fertilization-embryo secretes hCG which maintains the corpus luteum and its hormones secretions

uterus: hormones from the corpus luteum promote thickening of the endometrium 12-18 mm, endometrial glands and vascularization, mentrual phase begins if there is no fertilization

Question 28

What is the role of inhibin in the female reproductive cycle?

Answer 28

produced by corpus luteum, inhibits the secretion of FSH because if there is already a fertilized egg present we don’t ned to prepare another one

Question 29

What is the basic path of milk flow out of the breast?

Answer 29

alveoli
mammary duct
lactiferous sinus
lactiferous duct
nipple (with lactiferous openings)

Question 30

What are the important features of an alveolus?

Answer 30

contractile unit (around the ductile to force milk out)
myoepithelial cells (make up the contractile unit)
ductile (the channel that the milk flows through)
alveolus (makes up the walls of the ductile)

Question 31

Describe the concentration of hormones throughout the female reproductive cycle.

Answer 31

FSH: small peak at 12-14 days (ovulation)
LH: big peak at 12-14 days (ovulation)
estrogens: peak right before ovulation, causes the peaks in LH and FSH
progesterone: peaks 2 weeks after ovulation, stays high if the egg is fertilized and implants

Question 32

Low concentrations of estrogen in the presence of progesterone stimulates…

Answer 32

release of GnRH

Question 33

Draw a diagram of how the ovarian nd uterine cycles overlap (and the female reproductive cycle).

Question 34

How do female reproductive hormone levels change throughout life?

Answer 34

low in childhood, raise in puberty particularly at night, moderate in the reproductive years, and high during menopause