RED ARROWS (Robia) & UNDERLINED (Ozark) Flashcards
Meiosis II of ovum is completed at
fertilization (discontinuous)
Spermatogenesis results in how many germ cells
4
Oogenesis restults in how many germ cells
1
Normal sperm production requires
reduced temp
What receptor (and where) is upregulated in pregnancy promote cause GERD?
B-receptors on LES
What steroid hormone peaks during labor, and promotes partuition?
cortisol
What is progesterone’s role during pregnancy?
maintains uterine quiescence and sustains fetus
What is estrogen’s role during pregnancy?
Promotes partuition, increases sensitivity to OXY
Ovary development depends on presence of
2x and no y
loss of one x results in
ovarian dysgenesis but no lose of female ducts or genitalia (turners)
How is it possible to have XX male and XY female?
presence or absence of XY, respectively
What promotes relaxin? What does it do?
hCG promotes relaxin. It relaxes the pelvic bones (looser)…
XY without SRY looks like
turners
When male hormones are absent, default is
female genital tract, external genitals
What blocks 5-alpha reductase?
Propecia (finesteride)
XO is
turners
Seminifereous tubule dysgenesis disease
XXY klinefelters
What causes male pseudohermaphroditism
Androgen resistance
Main cause of congenital adrenal hyperplasia
21 hydroxylase deficiency
21 hydroxylase deficiency main cause of
CAH
Lack cortisol/aldosterone. Main cause
CAH - 21 hydroxylase deficiency
slide 21…
COME BACK TO THIS
clitoromegaly….retention of urogenital sinus and fusion of labia…these features are exhibited in
female pseudohermaphroditism … virilization by androgens….
T to E2
aromatase
T to DHT
5-alpha hydroxylase (blocked by propecia, finesteride)
Male pattern baldness caused by
DHT
What is the function of the intercellular bridges between secondary spermatocytes?
Synchronizes development, sharing resources…large enough to pass organelles by MT’s
What’s an acrosome?
A cap of membrane containing digestive enzymes
Continuous exposure (not pulsatile) of GnRH
inhibitory FSH and LH release
What keeps T high near developing sperm?
ABP from sertoli cells (which are stimulated by T and FSH)
Paracrine inhibin from sertoli does what to leydig?
PROMOTES it (opposite)
Paracrine activin from sertoli does what to leydig?
INHIBITS it (opposite)
Ovulatory phase
short 1-3 days, time of final oocyte maturation and release into reproductive tract. LH/FSH surge
as the follicular phase progresses, what happens to E2?
E2 synthesis from ovary increases past certain threshold, and SWITCHES from negative to positive feedback at ant. pituitary: LH SURGE.
What hormone is secreted at IMPLANTATION
hCG
Theca cells are analogous to sertoli cells. What enzyme is lacking in theca cells?
aromatase
Granulosa cells are analogous to leydig cells. What enzyme is not lacking?
aromatase. Androstenedione from theca cells can be made into E2
Describe ovulatory mucus secretions
Crystalized mucus looks like “Fern”
Most “stretch”
Female infertility quadruples between ages
20 and 40
Describe the acrosomal reaction
spermatozoan has receptors for glycoprotein of zona pellucida, called “ZP3”. binding causes increased IP3, leading to INCREASED CALCIUM, and membrane fusion, forcing enzyme rich contents out
Mechanism of polyspermy?
Sperm penetration promotes release of enzymes that harden glycoproteins of zona pellucida. Oocyte’s internal vesicles release hydrolytic enzymes that digest ZP2, altering the membrane to modified ZP3, which is HARDENED so polyspermy can’t occur
Ca2+ increase that caused cortical reaction also triggers
second meiotic division of oocyte
how many sperm actually arrive at the distal end of fallopian tube
50 or less
What is the failure rate of implantation
70%
What happens to the zona pellucida during adhesion of the zygote to uterine wall?
it dissolves
During adhesion stage of implantation, the blastocyst secretes _____ which increases integrins in endometrial cells
IL1
What does osteopontin do?
The embryo and the endometrium both have increased integrins. Osteopontins bridge the two integrin-rich interfaces during adhesion.
What do stream cells do, during adhesion?
stromal cells form decidua and SECRETE NUTRIENTS. Later this becomes a barrier and endocrine organ.
What is the role of the synctiotrophoblast?
Responsible for most endocrine functions “acts like pituitary”
What is the role of the cytotrophoblast?
Secrete CRH, TRH, and somatostatin “acts like hypothalamus”
Thick layer of well vascularized endometrium
ideal for implantation of embryo. Occurs during luteal phase. Maintained by progesterone from corpus luteum. If fertilization occurs, hCG from placenta maintains corpus luteum to maintain the endometrium
hCG from placenta
increases by LOG SCALE (a lot) and negatively regulates pituitary release of LH/FSH so another follicle doesn’t develop
What inhibits RPL
progesterone and estrogen during pregnancy, and dopamine
What happens to the size of fetal adrenal gland, as it starts cranking out DHEA-S for estrogen synthesis?
grows to 20x original size
Marker for fetal wellbeing? How is it made?
Estradiol.
Cholesterol from mom, is made into pregnenalone (via desmolase) in the placenta. The pregnenalone goes to the fetal adrenal gland, where it is converted to DHEA-S. DHEAS-S goes to fetal liver, where it becomes 16-OH DHEA-S. 16-OH DHEA-S then goes to the placenta, where it is made into Estriol.
Although estriol is the major estrogen during pregnancy, it has weak estrogenic activity.
What prevents premature lactogenesis?
High E2/Progesterone from the fetus
What happens to LES during pregnancy
decreased tone. more heartburn
Ferguson reflex
More distention of cervix, more OXY release, which promotes prostaglandin release, which promotes contractions.
Cortisol promotes
surfactant production in baby
What stimulates maternal behavior during pregnancy, and after birth? OXY or prolactin?
prolactin
Whale milk has what % fat?
40-65%
What are the two effects of prolactin?
Mammogenic (breast development)
Galactogenic (milk production)
Removing dopamine release inhibition on
prolactin secreting lactotrophs in anterior pituitary, promoting milk production
What does suckling do to GnRH
Inhibits arcuate and POA….decrease GnRH….
FSH stimulates which cells? Pick 2 A. Granulosa B. Sertoli C. Theca E. Leydig
Granulosa and sertoli
LH stimulates which cells? Pick 2
A. Granulosa
B. Sertoli
C. Theca
E. Leydig
C and E
Menarche. When usually occurs?
(First menses): usually between 11-14 yo in USA
What’s abnormal for menarche?
Menarche that’s more than 2.5 years after thelarche
What tanner stage do you get COURSE pubic hair (both men and women)
3
In the 2nd male tanner stage, testicular volume size increases by how much?
> 3mL
Describe precocious puberty in women
younger than 6 years old
Describe precocious puberty in men
younger than 9 years old
Primary amenorrhea
no menses by 16, or 2.6 years after thelarche
Secondary amenorrhea
absence of 3 consecutive cycles following the establishment of regular cyclic menstrual periods of 6 months of amenorrhea.
HYPERgonadotrophic hypogonadism
Low E2, high LH/FSH
Eg. Turner’s
HYPOgonadotrophic hypogonadism
Low E2, low LH/FSH
Eg. Kallmans
Eg. hypopituitary, infarct, stress
Abnormal gap in tanner stages
> 2 tanner stage difference
First sign of pubertal development in females
breast buds
Normal cycles depend on what kind of feedback
positive
