Periods, 101 Flashcards
Survival of ovum = ____ h
Survival of sperm = ____ h
6-12
24-48
Typical ejaculate =
vol: ___ mL
conc: ___ mil/mL
tot#: ___ mil
1-3
1
100-300
What mechanisms help to facilitate fertilization?
- timing (boners + female cycle)
- lots of sperm
3; cervical mucus thinning - increased motility of female tract
When does cervical thinning occur?
midcycle, due to estrogen
Female tract motility is enhanced by:
E2, PG, OT
Successful conception is most likely…
2 days before + day of ovulation
How does female age related to contraception?
decreased chance of preg after age 35 due to fewer follicles
___% of ova regress before puberty even happens.
70
When all ova are gone, ____ occurs
menopause
Menopause is associated with a decline in ____ and an increase in ___.
decreased estrogen
increased LH + FSH
The follicle secretes:
estradiol-17beta
androgen (from thecal cells)
progesterone
Granulosa cells make:
estrogen (from androgens)
inhibin
Thecal cells make:
androgens
FSH stimulates _____ cells.
LH stimulates _____ cells.
granulosa
thecal
Why does only ONE follicle function as the “dominant” follicle?
secretes a magical unknown substances which causes the other ovary and the surrounding follicles to regress
The _____ cells secrete inhibin, which feeds back to reduce secretion of _____.
granulosa
FSH
**note: this happens at end of follicular and during luteal phases
FSH increases during the menstrual cycle in response to:
loss of negative feedback by estrogen, progesterone and inhibin
What surges immediately before ovulation?
LH
and FSH, but it’s not a huge surge
When progesterone is high, what is going on in the dominant follicle?
it is turning into corpus luteum
What ovarian phase is prior to ovulation?
What ovarian phase is post-ovulation?
follicular
luteal
Following the menstrual phase…
What uterine phase is prior to ovulation?
What uterine phase is post-ovulation?
proliferative
secretory
Progesterone and estrogen levels both begin to decline around week ___ of cycle.
4
(thus very low while you’re actually bleeding; and yes, I know for you this like week 7 because your uterus is very nice)
How does basal body temp relate to the cycle?
increases 1’F following ovulation and remains elevated until menstruation
Menstrual phase lasts ___ days.
Proliferative phase lasts ___ days.
Secretory phase lasts ___ days.
~5
~11
~12
Estrogen acts via negative feedback on:
- hypothalamus, blocking release of GnRH
- FSH release
- LH release
Inhibin acts via negative feedback on:
- FSH release
2. Ant. pituitary
During the early follicular phase, granulosa cells secrete ___.
During mid-follicular phase this hormone acts on ___, which results in…
estrogen
granulosa cells to increase their proliferation (via + feedback)
Act w/in the follicle to promote cellular proliferation and hormone secretion (4)
inhibin
IgF-2
activins
VEGF
Granulosa cells in the late follicular phase have receptors for:
FSH
LH
How do thecal and granulosa cells cooperate?
- Thecal cells produce androgens, and use progenolone synthesized by granulosa cells
- Granulosa cells synthesize estradiol, using androgens synth by theca cells
Ovulation is triggered by:
LH surge
During ovulation, _____ ruptures after attack by ___.
follicular membrane
proteolytic enzymes
Variation in length of a woman;s cycle is caused by the length of the ______
follicular phase
Corpus luteum develops from _____, beginning (when?).
follicular cells
shortly before ovulation
How can you tell the corpus luteum has started developing (based on hormones)?
small increase in progesterone, which occurs at the end of the follicular phase
When does the CL degenerate?
last 5 days of the luteal phase
_____ +/- _____ inhibits FSH and LH secretion.
Inhibin +/- progesterone
What is luteolysis?
CL regression + degeneration
When does luteolysis occur?
day 8 after ovulation
What causes the decline in estrogen + progesterone?
degeneration of CL
Luteolysis can be prevented by:
stimulation with LH or hCG
hCG is produced/secreted by:
placenta, upon implantation of a blastocyst
Compared with midfollicular granulosa cells, luteinizing granulosa cells are producing:
progesterone
LH stimulation
Why does FSH and LH rise during menstruation?
estrogen, progesterone + inhibin decline, which removes negative feedback inhibition of LH/FSH
During menstruation, increased FSH/LH results in:
stimulation of growth of new follicles
which produce estrogen + some inhibin
What triggers the LH (+FSH) surge?
new follicles result in steadily increasing estrogen, which triggers LH/FSH surge via increased response of gonadotrophs to GnRH
Follicular phase in ovary corresponds to what phase(s) in endometrium?
menstrual + proliferative
Luteal phase in ovary corresponds to what phase(s) in endometrium?
secretory
You can induce ovulation in women with hypogonadotrophic hypogonadiam by giving them:
regular pulses of GnRH
which result in pretty normal estrogen and progesterone patterns
If ovulation doesn’t occur, what happens to CL?
still forms/develops + secretes E/P
cycle appears nml
An increased incidence of shorter luteal phases has been noted in:
- women who start a heavy workout program
- infertile women
- women w/ 1st trimester miscarriages
How are mammary gland cells affected by menstrual cycle?
increased mitotic rate in luteal phase
