Female Physiology Flashcards
In general, lack of hormonal signals leads to a____ phenotype; hormone signals are required to develop into the ____ phenotype.
female
male
absence of the Y chromosome leads to the development of the_____. The most important gene product in this regard is ________ which is now known to be encoded by the SRY (sex-determining region of the Y chromosome).
ovaries
H-Y antigen
Once the ovaries form, there is the lack of production of________ and__________
In the absence of these two hormones, the Wolffian ducts regress and the male genitalia do not form, and the mullerian ducts develop into the female reproductive tract.
androgens
mullerian- inhibiting factor
In males, androgens induce the development of the male internal and external genitalia, and_____ induces the regression of the mullerian ducts.
MIF
________from the placenta and fetal _______dramatically stimulate the production of oogonia within the ovaries (this occurs in the FETUS)
hCG (human chorionic gonadotropin)
FSH and LH
Between 2 and 6 months of post-natal age, ______peak again. The exact purpose of this is in females is not well established since the ovaries don’t respond; in males, this burst of gonadotropins does stimulate the testes to produce androgens.
FSH and LH
Before the first menstrual cycle (menarche), the____ secretes FSH and LH which induces ovarian function
pituitary
The pathways to DHEA and androstenedione are catalyzed by the _____ in the adrenal cortex.
same enzymes
17 alpha hydroxyprogesterone/prognenolone
Our three estrogens are produced by what enzyme from either testosterone or androstenedione
Aromatase
What are the primary secretory products of the ovary.
Estradiol and estrone
Estriol is usually only found in significant amounts in the blood in
pregnant women
GnRH pulses commence at about 9 years of age, what is the purpose?
This leads first to an increase in FSH and then LH. These restart ovarian follicular development and the production of estradiol by steroidogenic tissue. The increase in estrogen leads to (a) the growth spurt (see the growth hormone lecture), and the development of the secondary sex characteristics
the onset of menstrual cycles is usually the_______ occurrence during puberty._______ induces the closure of the growth plates in long bones and leads to an end to the growth spurt.
last
Estrogen
Understand peak of LH and FSH as well as estradoil in menstral cycle
If pregnancy does not ensue and____ is not released by the trophoblast into maternal blood, the corpus luteum dies and progesterone and estrogen decrease.
This loss of negative feedback leads to an increase in_____ that induces maturation of the next group of follicles
hCG
FSH
A dominant follicle forms (at about 4 days) and begins to release_____ autonomously which will decreases FSH (and LH) via negative feedback.
The decrease in FSH leads to :
estrogen
atresia of the non-dominant follicles
As the dominant follicle grows, it produces more and more estrogen, When estrogen peaks, it induces a switch in the hypothalamic-pituitary unit (at least in part due to kisspeptin release in the hypothalamus) from negative to positive feedback so that estrogen stimulates a surge in
LH
The _____stimulates ovulation and the formation of the corpus luteum.
LH surge
The corpus luteum produces enormous amounts of_____ and to a lesser degree estrogen, both of which inhibit LH and FSH secretion
progesterone