S2 Bsf Exam 3: Female Reproductive Physiology

Front 1

what marks the onset of puberty?

what marks the reproductive years?

what marks menopause?

Back 1

onset: gradual increase in LH and FSH

reproductive: cyclic release of LH and FSH

menopause: sustained high levels of LH and FSH

Front 2

what is the range for the start of female puberty? end?

Back 2

start: 8-9 yrs
end: 11-16 yrs

Front 3

what does a pulsatile release of GnRH result in?

what sex characteristics are involved in this stage in life?

Back 3

START of Puberty! (male & female)
= pulsatile LH and FSH release leading to an increase in estrogen and androgens from the ovary;

primary sex characteristics

Front 4

what is menarche?

Back 4

beginning of menstrual cycles.

Front 5

what are the two secondary sex characteristics?

Back 5

Thelarche (breast development) and
adrenarche (increase in androgen secretion)

Front 6

what is thelarche due to?

what is adrenarche due to?

Back 6

thelarche: presence of estrogen

adrenarche: pubic hair growth (androgens & DHEA)

Front 7

why does the growth spurt occur earlier in females than males?

Back 7

earlier onset of GnRH release

Front 8

what are the metabolic actions of estrogen on protein, lipids and epiphyseal plate?

Back 8

protein: anabolic (build)

lipid: anti-lipolytic (promotes fat storage)

epiphyseal: stimulates closure = end of female height growth at puberty

Front 9

what is the last step in female puberty? what does this result in?

Back 9

hypothalamic pituitary ovarian axis; decrease in sensitivity of the gonadotrophs to feedback inhibition by estrogen.

Front 10

what is a functional unit of the ovary?

Back 10

the ovarian follicle
= one germ cell completely surrounded by a cluster of endocrine cells.

Front 11

Upon development, what 5 functions does the ovarian follicle have?

Back 11

1) maintains & nurtures oocyte
2) matures the oocyte & releases it at the appropriate time
3) prepares vagina & fallopian tubes to assist in fertilization
4) prepares uterus to accept & implant zygote
5) maintains hormonal support of the fetus until placenta takes over.

Front 12

by the 5th month of gestation, how many primary oocytes does the female have?

How many have undergone atresia?

Back 12

7 million;


>6 million follicles

Front 13

how many primordial follicles are in ovarian reserve at menarche (onset of puberty)?

how many ovarian follicles at this time undergo atresia?

Back 13

<300,000;


>270,000 follicles

Front 14

how many ovarian follicles are present at ovulation?

Back 14

<500 follicles


*recognize atresia is always occuring, decreasing # of follicles throughout life

Front 15

when does mitosis occur in oogenesis?

Back 15

5-6 wks of gestation (starts w/ primordial germ cells)

Front 16

what happens from 8-9 wks to 6 months after birth?

Back 16

some oogonia enter prophase of meisosis I and become primary oocytes and remain in prophase I until sexual maturity.

Front 17

when do primary oocytes become primordial follicles?

Back 17

once a layer of granulosa cells surrounds the oocyte and a basil lamina is formed on the outside of the granulosa cells.

Front 18

what characterizes the formation of a secondary follicle form a primary follicle?

When does this occur?

Back 18

addition of the thecal layer of cells


AFTER puberty

Front 19

what is post pubertal follicular development under control of?

Back 19

cyclic FSH release

Front 20

when does graafian follicle development begin?


how many days are required for Graafian follicle development?

Back 20

at puberty and continues in a ~28 day cycle


70-85 days, occurs AFTER menarche

Front 21

what is formed when the vesicles of the secondary follicle coalesce? what is it rich in?

Back 21

fluid filled antrum that is rich in estrogen produced by the granulosa and thecal cells.

Front 22

what happens to the oocytes inside the antrum?


what is this specific area called?

Back 22

it is pushed to one side and sits on a cluster of granulosa cells;

cumulus oophorus

Front 23

when does the oocyte officially reside within the Graafian follicle?

Back 23

when the oocyte sits in the cumulus oophorus

Front 24

what happens to the follicular volume as the follicle grows? what is formed because of this?

Back 24

it increases and swells; theca cells are stretched and a blister like bulge is formed.

Front 25

what is the most rapid stage of oogenesis?

how long does it last?

Back 25

selection for ovulation, lasting 7-10 days

Front 26

what hormone is ovulation under?

Back 26

LH

Front 27

what determines which Graafian follicle is selected for ovulation?

Back 27

the number of estrogen and FSH receptors

Front 28

what does the 1st meiotic division at ovulation yield?

Back 28

secondary oocyte and 1st polar body

(^from primary oocyte in prophase 1)

Front 29

what phase is the secondary oocyte suspended in when it begins the 2nd meiotic division at ovulation?

Back 29

metaphase II

(*will not go any farther through meiosis 2 UNLESS fertilized!!)

Front 30

where does the secondary oocyte go to after ovulation?

Back 30

it travels down the ampulla of oviduct

Front 31

what completes the 2nd meiotic division?

what is formed?

Back 31

the sperm penetration of the zona pellucida

forms an ootid and the 2nd polar body which degenerates.

Front 32

what is the remaining follicle at rupture (after 2nd polar body deteriorates)?

Back 32

corpus hemorrhagicum

Front 33

what forms the corpus luteum?

under what influence?

Back 33

under the influence of LH, the granulosa and theca interna cells form the corpus luteum.

Front 34

what does the corpus luteum produce?

when does the corpus luteum persists?

what does it become if it does not persists?

Back 34

progesterone;

persists if pregnancy ensues

if not it becomes the corpus albicans (white body) at the end of the luteal phase.

Front 35

what is atresia?

Back 35

the process by which any stage follicle degenerates and dies.

Front 36

why isn't meiosis completed in an oogonium?


Which phase is the primary oocyte arrested in?

Back 36

it begins, but it can't be completed because the levels of proteins required to complete are too low.

prophase 1 of meiosis 1
(will remain in phase until ovulated, up to 50 yrs)

Front 37

what happens as the primary oocyte grows?
what maintains the arrested state?

Back 37

it synthesizes proteins required to complete meiosis, but high cAMP levels actively maintain the arrested state.

Front 38

what happens to the primary oocyte just prior to ovulation? what phase is it arrested at?

Back 38

the oocyte completes meiosis I and extrudes 1st polar body.

Arrested at metaphase II (meiosis 2)
(secondary oocyte will complete meiosis if fertilized)

Front 39

T/F
ovarian sex steroids provide both positive and negative feedback

Back 39

true

Front 40

what stimulates the follicular phase of estrogen and activin (from ovary)?

Back 40

PKC

Front 41

what does an increase in calcium release trigger in the hypothalmic pituitary ovarian axis?

Back 41

exocytosis and release of gonadotropin.

Front 42

what receptor is expressed by granulosa cells? what are the functions of the granulosa cells? what cells are these similar to that are found in males?

Back 42

express FSH receptor; provide a protective nursing function -> sertoli cells

Front 43

what receptor is expressed by thecal cells? where are they found and what do they produce? what cells are they similar to that are found in males?

Back 43

expresses LH receptor; they are found outside the nurse cells and produce androgens. they are similar to leydig cells.

Front 44

what makes granulosa cells different from sertoli cells? what does that make the granulosa cell dependent on?

Back 44

they lack the enzyme for conversion to androstenedione. (17 alpha hydroxylase); making granulosa cell dependent on the theca cell in order to make testosterone or estrogen.
(theca cell CANNOT make estrogen itself)

Front 45

T/F
For the production of progesterone, you need both the theca cell and the granulosa cell.

Back 45

FALSE.

either one can produce progesterone on their own.

Front 46

what are the six steps in estrogen formation?

Back 46

1) LH stimulates theca cells (via cAMP) to increase synthesis of LDL & HDL receptors & side-chain cleavage enzyme
2) theca increases synthesis of androstenedione
3) androstenedione freely diffuses to granulosa cells
4) FSH (via cAMP) stimulates granulosa cell to produce aromatase
5) aromatase converts androstenedione to estrone & 17B HSD converts estrone to estradiol
6) estradiol diffuses into blood vessels

Front 47

when does FSH induce expression of LH receptors on granulosa cells? what is the purpose of this?

Back 47

in late follicular phase;
allows granulosa cells to maintain high levels of aromatase as FSH falls & ensures that cells will respond to the LH surge (increases LH sensitivity).

Front 48

what two organs are involved in the menstrual cycle?

Back 48

ovary and uterus

Front 49

what separates the follicular and luteal phases (ovarian phases)?

Back 49

ovulation

Front 50

what are the three phases involved with the uterus?

Back 50

menstrual, proliferative and secretory
= endometrial cycle

Front 51

what does the monthly pattern result from?

Back 51

the interaction of ovarian steroids and peptides and their ability to exert both positive and negative feedback on the hypothalamus and pituitary.

Front 52

when does the follicular phase begin? what is the average length of this phase?

Back 52

begins with onset of menstrual bleeding; average ~15 days


(*ends w/ peak in LH)

Front 53

what is the most variable part of the menstrual cycle?

Back 53

follicular phase

Front 54

How long does the ovulatory phase last? when does it culminate?

Back 54

lasts 1-3 days and culminates in ovulation

Front 55

how long does the luteal phase last? what does it end with?

Back 55

lasts 13-14 days, ends with menstrual bleeding



(bleeding starts-->follicular-->ovulatory-->luteal)

Front 56

best way to figure out ovulation?

Back 56

onset of menstrual bleeding - 14 days

Front 57

what is the follicular phase of the ovarian cycle characterized by?

Back 57

recruitment & growth of 15-20 antral follicles with growth of a dominant follicle until ovulation

Front 58

During follicular phase, inhibin, estrogen, & progesterone are (high/low)

Back 58

low

Front 59

what releases gonadotroph? what does it result in?

Back 59

released from lack of negative feedback (low estrogen, inhibin)

results in an increase in FSH secretion

Front 60

in early follicular phase, what does the rise in FSH recruit? what is produced because of this?

Back 60

a crop of large antral follicles that begin rapid, FSH dependent growth. these antral follicles produce low levels of estrogen and inhibin B.

Front 61

what affect does rising estrogen and inhibin B have on FSH secretion?

Back 61

negative feedback

Front 62

what ratio is increased during follicular phase?

Back 62

LH/FSH

Front 63

what does a decrease in FSH lead to?

Back 63

atresia of developing folicles except one dominant follicle (one w/ most FSH receptors)

Front 64

what does the dominant follicle produce in late follicular phase?

Back 64

increasing amount of estrogen and inhibin B.

also some progesterone 2-3 days prior to ovulation

Front 65

what affect does High estrogen with little progesterone have?

Back 65

Positive effect LH on FSH

Front 66

what induces ovulation?

Back 66

LH surge

Front 67

an increase in FSH will cause in increase in what type of receptors? what does that aid in?

Back 67

increase in the number of LH receptors. This will augment granulosa and theca cell responsiveness to LH.

Front 68

what hormone does the dominant follicle become the primary producer of?

Back 68

estradiol

Front 69

what is secreted by the dominant follicle near the end of the late follicular phase? what does this promote and mean?

Back 69

Estrogen is secreted and it promotes positive feedback of ant pituitary sensitizing it to GnRH. Thsi signals HPA that follicular development is complete

Front 70

why does the LH surge terminate?

Back 70

due to loss of positive feedback of estradiol and increase in progesterone (decreased ratio E/P)

Front 71

what three events (in order) are driven by the LH surge in the ovary?

Back 71

1. Primary oocyte completes meiosos I & arrests in metaphase of meiosis II.
2, Wall of follicle & ovary broken down with release of cumulus-oocyte (ovulation)
3. Granulosa and thecal cells are restructured to form corpus luteum (CL). (CL is vascularized)

Front 72

what is initially decreased in early luteal phase?

what affect does this have on LH?

Back 72

initial drop in estrogen terminating the positive feedback on LH (bc E/P ratio is decreased)

Front 73

what causes an increase in progesterone and estrogen?

what does this lead to?

Back 73

maturation of the corpus luteum

a negative feedback on both LH and FSH

Front 74

what starts to regress in late luteal phase? what does that lead to?

Back 74

corpus luetum; decrease in P and E

Front 75

if no fertilzation occurs, what will regress,
what three things will be kept low,
and what will be released?

Back 75

regress: corpus luteum
low: E, P, and inhibin
released: gonadotroph is released from negative feedback resulting in an increase in FSH secretion

*menses occurs & cycle begins again

Front 76

what phase does the proliferative stage coincide with?

Back 76

follicular phase

Front 77

what do rising estrogen levels in mid- to late follicular phase induce?

Back 77

all cell types in the stratum basale to grow and divide.

Front 78

in what phase does the endometrial lining start to grow?

Back 78

proliferative stage

Front 79

cell proliferation in the proliferative phase occurs directly via what receptors?
indirectly thru production of what?
what will that cause?

Back 79

directly: estrogen receptors
indirectly: production of growth factors
causes: arteries become more abundant & uterine glands to form.

Front 80

what does estrogen induce the expression of in the proliferative phase? what does this do to the uterus?

Back 80

induces expression of progesterone receptors "priming" the uterus to respond to progesterone during the luteal phase of the cycle.

Front 81

what is the secretory phase preparing for?

Back 81

implantation

Front 82

what two steroids are driving the secretory phase? what phase does it coincide with?

Back 82

driving: progesterone and estrogen
coincides: luteal phase

Front 83

what does progesterone induce in the secretory phase?

Back 83

-uterine glands to fill with glycogen vacuoles to support the embryo
-differentiation of epithelial and stromal cells.
-conversion of active estradiol to inactive estrone (important for protecting the endometrium from estrogen induced uterine cancer)

Front 84

what does progesterone inhibit in the secretory phase?

Back 84

endometrial growth.
It opposes the proliferative actions of Estrogen by down-regulating the ER.

Front 85

what is lost because of menstruation?

Back 85

lamina functionalis and uterine lining

(& 25-35 ml blood)

Front 86

what is the implantation window?

Back 86

a brief time period of endometrial receptivity for implantation (fertilization)

(only effective >4 days)

Front 87

during the menstrual cycle, what changes occur with the oviduct?

Back 87

increase the muscular and ciliary activity for egg, sperm and zygote transfer

Front 88

during the menstrual cycle, what does estrogen stimulate in the vagina?

Back 88

proliferation of epithelium and increases the cells glycogen content (good for sperm)

Front 89

later during the menstrual cycle, what does P stimulate in the vagina?

Back 89

increases desquamation of the epithelial cells & breakdown of glycogen. This aids in the maintenance of the acidic environment of the vagina. (bad for sperm, prevents infection)

Front 90

which steroid is responsible for an increase in basal body temp?

Back 90

progesterone

Front 91

what affect does estrogen have on the cervix?

Back 91

it stimulates the production of thin, slightly alkaline mucus that create an ideal environment for sperm.

Front 92

what affect does P have on the cervix?

Back 92

stimulates production of scant, viscous, acidic mucus that does not promote sperm.

Front 93

what affect does estrogen have on the breasts?

Back 93

enhances duct growth

Front 94

what affect does Progesterone have on the breasts?

Back 94

responsible for alveolar development

Front 95

what affect does estradiol 17B have on bone?

Back 95

epiphyseal plate closure*
-stimulates intestinal Ca absorption & renal re-absorption
-Promotes survival of osteoblasts & apoptosis of osteoclasts favoring bone formation.

Front 96

what affect does estrogen have on the liver?

Back 96

*decreases circulating LDL, increases HDL

(Increases expression of LDL receptor for enhanced clearance)

Front 97

what affect does estrogen and progesterone have on the integument?

Back 97

maintain healthy skin (both)*
-increase collagen synthesis in the dermis and suppress matrix metalloproteases (both)
-increases glycosaminoglycan production & promotes wound healing (E)

Front 98

what affect does estrogen have on the cardiovascular system?

Back 98

it promotes vasodilation via increased production of nitric oxide.

Front 99

what affect does estrogen and progesterone have on the CNS?

Back 99

estrogen: neuroprotective (inhibits neuronal cell death in response to hypoxia or other insults). increases angiogenesis.
decreases degradation of serotonin (elevates mood)

progesterone: acts on hypothalamus to elevate body temp.
increase MOA concentration (serotonin degrad)(depression & irritability)

Front 100

what affect does P have on the kidneys?

Back 100

it is a competitive inhibitor of aldosterone and it has a natriuretic action on the kidney.

Front 101

what affect does estrogen and progesterone have on the adipose tissue?

Back 101

lipolytic effect. Loss of estrogen results in accumulation of adipose esp in abdominal area.

Front 102

what percentage of estrogen is bound to the sex hormone binding globulin (SGBG)?
albumin?
is considered free estrogen?

Back 102

60%;
20%;
20%

Front 103

what does progesterone bind to? with what kind of affinity? what is the circulating half life?

Back 103

cortisol binding globulin or albumin; with low affinity; 5 min

Front 104

where does peripheral aromatization of androgens to estrogen occur?

Back 104

tissues that have high levels of a aromatase (like breast tissue)

(androgen from kidneys is converted to estrogen)

Front 105

what are E and P conjugated with in liver?

Why?

Back 105

conjugated in the liver with sulfate or glucuronide.

to be excreted in urine

Front 106

why do E and P pass thru cell membranes?

Back 106

to bind to ER (estrogen) or PR (progesterone) receptors in the cytosol

Front 107

what are the unbound receptors complexed with?

what dissociates the receptors from these proteins?

Back 107

chaperone proteins;

ligand binding

Front 108

when does female libido increase? why?

Back 108

around the time of ovulation due to an increase secretion of androgenic steroids just before and during ovulation.

Front 109

where is the erectile tissue similar to that of the penis located on the female? what type of nerves control it?

Back 109

around the introitus and extending to the clitoris; parasympathetic nerves.

Front 110

what happens when the blood vessels dilate in erectile tissues? what does it do to the vaginal opening?

Back 110

dilation causes engorgement and erection of clitoris and distention of the peri-introital tissue. This narrows the lower 1/3 of the vaginal opening.

Front 111

what else does the PNS innervate that corresponds with the female sex act?

Back 111

the bartholin's glands which secrete mucus immediately inside the introitus providing lubrication.

Front 112

What is a female orgasm analogous to in males? what type of nerves control those acts?

Back 112

emission (sympathetic) & ejaculation (spinal reflex)

Front 113

during an orgasm, what contracts that may aid in the transport of sperm? how long is the cervical canal dilated?

Back 113

perineal muscles contract rhythmically; dilated up to 30 minutes to aid in sperm transport.


GET YOUR GIRL OFF FIRST DUH

Front 114

what does the pituitary secrete at the time of an orgasm? why?

Back 114

oxytocin- this causes increased uterine contractility which facilitates gamete transport.

Front 115

what is resolution in the female sex act?

Back 115

a return to normal, pre-excitement, physiology

Front 116

what signals the end of menses and childbearing?

Back 116

menopause of the climacteric

Front 117

how does the loss of functional follicles cause menopause?

Back 117

level of ovarian steroids fall (E and P) and Gonadotropin levels rise (LH and FSH) bc no longer neg feedback by E & P