repro Flashcards
sources of estrogen?
ovary (makes 17beta estradiol)
placenta (makes estriol)
adipose (makes estrone via aromatization of androgens)
potency of estrogens?
estradiol > estrone > estriol
changes in estrogens during preg?
1) estradiol and estrone increase 50x
2) estriol increases 1000x = measure of fetal well being
sources of progesterone?
corpus luteum
placenta
adrenal cortex
testes
functions of progesterone?
endometrial glandular and spiral artery dvlpmt pregnancy maintenance decreased myometrial contraction thick cervical mucus increased body temp inhibit FSH, LH decreased estrogen receptor expression
lengths of phases of menstrual cycle?
follicular: can vary
luteal: always 14 days
when is follicular growth fastest?
2nd week of proliferative phase
what is the cellular mechanism underlying menstruation?
apoptosis of endometrial cells
when do 1ary oocytes develop, and when do they arrest?
start meiosis I during fetal life
arrest in prophase I until ovulation
when do 2ary oocytes develop, and when do they arrest?
resume meiosis after ovulation
arrest in metaphase II until fertilization
how long between ovulation and fertilization/degeneration?
1 day!
hormonal changes at ovulation?
increase in estrogen
increase in GnRH rcptrs on ant pit
LH surge –> ovulation
when does implantation happen?
6 days after fertilization
when is hCG detectable?
in blood: 1 week after conception
in urine test: 2 weeks after conception
what do you need for lactation?
1) prolactin –> induces and maintains milk production, inhibits gonadotropins
2) oxytocin –> promotes milk letdown, uterine contractions
** both prolactin and oxytocin stimulated by suckling
what is in breast milk?
IgA, macrophages, lymphocytes
** decreased infx, risk of asthma/allergies/DM/obesity
how does breastfeeding affect the mom?
reduces risk of breast and ovarian cancer
causes of increased hCG?
multiple gestations
hydatidiform moles
choriocarcinoma
Down’s
causes of decreased hCG?
ectopic/failing preg
Edward
Patau
when does the corpus luteum degenerate?
8-10 weeks - placenta starts making own E and P
how does smoking affect menopause onset?
menopause earlier in smokers
how to you test for menopause?
high levels of FSH are specific - bc low E –> lack of negative feedback
when does spermatogenesis start?
puberty!
spermatogonia are first stage (diploid, pre-replication)
how long does spermatogenesis take?
2 months
spermatid vs spermatozoon?
spermatid = product of meiosis I/II spermatozoon = mature - went through spermiogenesis, lost cytoplasm and gained acrosomal cap, etc
source of androgens?
testis: DHT and testosterone
adrenal: androstenedione
potency of androgens?
DHT > T > androstenedione
how does T affect bones?
causes closure of epiphyseal plates
** via E –> T aromatization
what converts androgens to estrogens in males?
CYP450 aromatase - in adipose and testis
what converts androgens to estrogens in females?
1) theca interna cells: cholesterol to androgens via desmolase (promoted by LH)
2) granulosa cells: androgens to estrogens via aromatase (promoted by FSH)
functions of DHT?
early: differentiation of penis, scrotum, prostate
late: prostate growth, balding, sebaceous gland activity
