Female Reproductive Physiology - Meininger

Question 1

What causes the most change in steroid hormone production in girls?

Answer 1

Steroid hormone production results more from changes in the number or sensitivity of receptors on target cells than from changes in gonadotropin concentrations

Question 2

What are the gonadotropins?

Answer 2

1) FSH

2) LH

Question 3

What are the two modes of gonadotropin release?

Answer 3

1) tonic mode

2) surge mode

Question 4

What is tonic mode?

Answer 4

1) similar to males

2) low but pulsatile release of LH

Question 5

What is surge mode?

Answer 5

1) unique to females

2) periodic massive release of LH (ovulation)

Question 6

Which set of ducts gives rise to the female reproductive system?

Answer 6

Mullerian ducts

Question 7

What is the difference between male and female duct system development?

Answer 7

1) females duct system development is independent of gonadal hormones (no ovaries necessary)
2) males need testes for their development

Question 8

Where are the sites of ovarian hormone production?

Answer 8

Ovarian follicles

Question 9

What do the ovarian follicles contain?

Answer 9

1) oocyte
2) layers of supporting cells
3) proper hormonal environment

Question 10

What kind of follicles are females born with and how do they progress?

Answer 10

1) born with primordial follicles

2) convert to primary follicles throughout life (independent of gonadotropins)

Question 11

What step of prophase are primary oocytes arrested in until ovulation?

Answer 11

primary oocytes are arrested in prophase of meiosis I until ovulation

Question 12

What arrests primary oocytes in Prophase of Meiosis I ?

Answer 12

Granulosa cell derived oocyte maturation inhibitor in the follicular fluid

Question 13

What triggers the resumption of meiosis at ovulation?

Answer 13

LH via blockage of the inhibitor

Question 14

The way gametes in the female develop…

Answer 14

episodically

Question 15

How many follicles ovulate?

Answer 15

One

Question 16

What happens to the follicles that are recruited but aren’t ovulated?

Answer 16

1) arrested in an immature state

2) undergo degeneration (atresia)

Question 17

What proliferates early in the development of the follicle?

Answer 17

1) Granulosa cells

2) the acquire FSH receptors and produce estrogen in response to FSH

Question 18

What are the steps in follicle development?

Answer 18

1) granulosa cell proliferation
2) further granulosa cell proliferation
3) accumulation of fluid within the follicle
4) formation of the antrum
5) ovulation - follicle ruptures and the ovum is released
6) remaining cells undergo luteinization and form the corpus luteum

Question 19

What cells have FSH receptors?

Answer 19

Only granulosa cells

Question 20

What are the main hormone products of the ovary and what produces them?

Answer 20

1) estradiol - by the follicle

2) progesterone - corpus luteum

Question 21

What hormones are made in small amounts by the ovary?

Answer 21

1) androgens
a) DHEA
b) androstenedione

Question 22

What hormones are made by the granulosa cells?

Answer 22

1) peptide hormones
a) inhibins
b) activins
2) released into follicular fluid and general circulation

Question 23

Where else is inhibin made besides in granulosa cells?

Answer 23

1) corpus luteum

2) post ovulation

Question 24

What hormones cause follicular develop after the antral phase?

Answer 24

FSH and LH

Question 25

What are FSH required for?

Answer 25

1) follicular development 2) ovulation 3) luteinization 4) steroid hormone synthesis

Question 26

What constitutes the ovarian cycle?

Answer 26

1) follicle development 2) ovulation 3) formation and degeneration of corpus luteum

Question 27

What is the follicular phase?

Answer 27

1) part of the cycle involving follicle development | 2) about 14 days but has variation

Question 28

What is the luteal phase?

Answer 28

1) the last 14 days of the cycle fominated by the corpus luteum 2) lasts 14 days and is not variable

Question 29

When does ovulation occur?

Answer 29

mid-cycle

Question 30

What are the primary jobs of FSH and LH?

Answer 30

1) FSH - stimulating growth of ovarian follicles | 2) LH - controls ovulation and regulates steroidogenesis

Question 31

What are the two important female sex steroids?

Answer 31

1) estradiol - product of the follicle | 2) progesterone - corpus luteum

Question 32

What is the sequence of hormonal changes during the ovarian cycle?

Answer 32

1) FSH bump stimulates ovary 2) development of about 10 follicles 3) rising estrogen and inhibin levels supres FSH secretion 4) one dominant graafian follicle emerges and produces even more estrogen 5) peak estrogen levels stimulate secretion of LH and FSH - mid cyclic LH surge 6) ovulation 7) corpus luteum leads to progesterone production 8) if no hCG produced by the fetus to sustain corpus luteum - it regresses and progesterone and estrogen levels fall 9) FSH inhibition falls with decreased estrogen and progesterone - FSH bump.....

Question 33

What do granulosa cells secrete and in response to what?

Answer 33

secretes estrogens in response to FSH

Question 34

What does development of the follicle depend on?

Answer 34

production of estrogen from granulosa cells in response to the FSH bump

Question 35

What kind of feedback is seen with estrogen and granulosa cells?

Answer 35

Positive feedback - estrogen promotes proliferation of granulosa cells and increases their responsiveness to FSH

Question 36

What does estrogen and FSH do to granulosa cells?

Answer 36

induces granulosa cells to synthesize LH receptors and acquire sensitivity to LH

Question 37

Where are LH receptors found before the antrum forms?

Answer 37

only on thecal cells

Question 38

What effect does LH have on thecal cells?

Answer 38

stimulates them to produce steroids

Question 39

What determines which follicles gets ovulated?

Answer 39

thecal cells surrounding this follicle become more sensitive to LH than other - higher receptor density

Question 40

When do LH receptors appear on thecal cells and granulosa cells?

Answer 40

1) Thecal cells - at an early stage | 2) granulosa cells - only in maturing follicle under the influence of FSH and estrogen

Question 41

Why can't granulosa cells produce estrogens and what does it need the thecal cells for?

Answer 41

1) deficient in androgen producing enzymes | 2) rely on diffusion of androgens from thecal cells to produce estrogens

Question 42

How do granulosa cells produce estrogens?

Answer 42

they produce aromatase in reponse to FSH and convert thecal derived androgens to estrogens

Question 43

What enzymes are missing from the granulosa cell and what is its consequence?

Answer 43

1) 17 alpha hydroxylase and 17,20 desmolase | 2) can't convert progesterone to androstenedione (gets it from thecal cell)

Question 44

What can't the thecal cell do?

Answer 44

It doesn't have aromatase activity so it can't convert testosterone to estrogens

Question 45

What is the function of granulosa cells to the oocyte and what is it analogous to in the male?

Answer 45

1) provides nutrients for oocyte development | 2) analogous to the nurse like function of sertoli cells

Question 46

What causes the release of the ovum from the follicle?

Answer 46

occurs as a result of proteolytic enzyme release from granulosa cells in response to LH

Question 47

What are the role of progesterone and prostaglandin formation in ovulation?

Answer 47

1) stimulate further production of proteolytic enzymes to break down follicle wall 2) contractile events to facilitate extrusion of the ovum

Question 48

What changes in granulosa cells when they become lutenized?

Answer 48

1) they have acquired their LH receptors 2) shift steroid production to progesterone 3) aromatase activity decreases and less estrogen is made

Question 49

What keeps corpus luteum functioning and why does it have a limited lifespan?

Answer 49

1) maintenance of steroid production by corpus luteum depends on continued stimulation by LH 2) limited life due to decreased sensitivity to LH

Question 50

How long does corpus luteum last?

Answer 50

1) it will regress after two weeks (even with continued LH stimulation) 2) only pregnancy and hCG rescues it

Question 51

How does estrogen prime target tissues for progesterone?

Answer 51

1) induces progesterone receptor synthesis 2) progesterone accelerates the turnover of estrogen receptors in the same tissues and decreases their response to estrogens

Question 52

What are the three phases of the uterine or endometrial cycle?

Answer 52

1) menstrual 2) proliferative 3) secretory

Question 53

What does the proliferative phase of the uterine cycle correlate with in the ovarian cycle?

Answer 53

mid to late follicular phase

Question 54

What happens to the uterus during the proliferative phase and what causes it?

Answer 54

1) under the influence of rising estrogen | 2) endometrium increases in size, thickness, glands elongate and becomes vascularized

Question 55

When does the secretory phase of the uterine begin and what ovarian phase does it correlate with?

Answer 55

1) begins of the day of ovulation | 2) coincides with early to mid luteal phase of ovarian cycle

Question 56

What happens to the uterus during secretory phase and what causes it?

Answer 56

1) progesterone and estrogen | 2) endometrial glands secrete large amounts of mucus and the stroma increases in vascularity and becomes edematous

Question 57

When is the peak thickness of the uterus?

Answer 57

1) 6-8 days after ovulation | 2) preparation for the implantation of the zygote

Question 58

What initiates the menstrual phase of he uterine cycle?

Answer 58

declining levels of steroids resulting from corpus luteum regression

Question 59

What happens in the uterus during the menstrual phase?

Answer 59

1) necrotic changes occur in the mucosal layer due to constriction of blood supply to the endometrium 2) desquamation and sloughing of the entire functinal layer of the endometrium 3) destablization of lysosomal membranes resulting in liberation of proteolytic enzymes and increased production of prostoglandins 4) prostaglandins cause vasospasm of the arteries while enzymes digest tissue - eventually blood vessels rupture

Question 60

What are the stages of the menstrual cycle?

Answer 60

1) follicular phase - first half - dominated by growing follicles that secrete estradiol 2) luteal phase - second half - dominated by corpus luteum that secretes progesterone 3) ovulatory phase is a short period in the middle of the cycle when the LH surge occurs 4) luteal phase is relatively constant due to fixed life span of the corpus luteum