Menstrual Cycle & Ovulation

Question 1

what are the main hormones associated with the menstrual cycle?

Answer 1

FSH
LH
estrogen
progesterone
inhibin

Question 2

what are the phases of the ovarian cycle?

Answer 2

follicular phase

luteal phase

Question 3

what are the phases of the endometrial cycle?

Answer 3

menses
proliferative phase
secretory phase

Question 4

where specifically do oocytes arrest FIRST? and when does this arrest resume? what hormone causes this?

Answer 4

prophase I
ovulation
LH

Question 5

where specifically do oocytes arrest the SECOND time? what causing the resuming of meiosis?

Answer 5

metaphase II

fertilization

Question 6

what surrounds the primary oocyte as a primordial follicle?

Answer 6

a single layer of pregranulosa cells

Question 7

what surrounds the primary oocyte as a primary follicle?

Answer 7

a single layer of more cuboidal granulosa cells

zona pellucida

Question 8

what surrounds the primary oocyte as a secondary follicle?

Answer 8

3-6 layers of cuboidal granulosa cells

Question 9

at what stage can release of paracrine factors first be observed in the follicle?

Answer 9

secondary follicle

Question 10

thecal cells are analogous to which types of cells in the male testes? what receptors do they express?

Answer 10

Leydig cells

LH

Question 11

what types of receptors do granulosa cells express depending on paracrine growth factors?

Answer 11

LH

FSH

Question 12

the antral phases results in proliferation and differentiation of which types of cells?

Answer 12

granulosa

Question 13

what are the two types of granulosa cells that develop during the beginning of the antral phase?
what are the main functions of these cells?

Answer 13

mural (outer wall of follicle/steroidogenic)

cumulus (maintain gap and adhesion jxns with oocyte)

Question 14

when is an antrum visible with the follicular cells?

Answer 14

after the secondary follicle

Question 15

what is the major product of thecal cells?

Answer 15

androstenedione

Question 16

at what point do follicle cells start to become responsive to gonadotropins?

Answer 16

antral phase after the secondary oocyte

Question 17

which cells produce androgens?

thecal
granulosa

Answer 17

thecal

Question 18

which cells aromatize androgens?

thecal
granulosa

Answer 18

granulosa

Question 19

what contributes to selection of antral follicles during each cycle? describe this process

Answer 19

FSH sensitivity

less and less FSH is released; bigger cells with more FSH receptors are selected to continue, the others die

Question 20

what is a graffian follicle?

Answer 20

follicle selected by FSH concentration

Question 21

when does the LH surge occur and what are its effects?

Answer 21

about 36 hours before ovulation
induces differentiation of granulosa cells to granulosa lutein cells
inhibition of aromatase expression
increased availability of cholesterol for progesterone production

Question 22

what causes the oocyte to progress to metaphase II?

Answer 22

LH surge

Question 23

what phase of ovulation follows the surge of LH?

Answer 23

luteal phase

Question 24

what are the two fates of the corpus luteum?

Answer 24

OF MENSTRUATION; becomes corpus albicans and is shed

OF PREGNANCY; rescued by hCG from conceptus, produces increasing progesterone

Question 25

what is the function of progesterone release by the corpus luteum?

Answer 25

transforms uterine lining into adhesive and supportive structure; important for implatation

Question 26

what is the function of progesterone and estrogen as related to LH?

Answer 26

reduce LH to basal levels to prevent another follicle from forming after fertilization

Question 27

what is the function of inhibin A as related to FSH?

Answer 27

suppress FSH to prevent another follicle from forming after fertilization

Question 28

which cells persist and repopulate the cellular stroma of the ovary after follicular atresia? granulosa oocytes thecal

Answer 28

thecal

Question 29

describe the HPO axis for gonadotropin release

Answer 29

GnRH from hypothalamus --> FSH and LH from anterior pituitary --> estrogens and progestins released from ovary (+activin and inhibin release from granulosa cells)

Question 30

which which cells produce inhibin/activin and what hormone do they feedback upon?

Answer 30

granulosa | FSH

Question 31

______ exert negative feedback at both low and high concentrations ______ are only effective at high concentrations

Answer 31

estrogens | progestins

Question 32

what is the net effect of estrogen and progestrin feedback on the HPO axis?

Answer 32

reduce LH and FSH release from the anterior pituitary

Question 33

when in the menstrual cycle is negative feedback occuring?

Answer 33

the whole thing

Question 34

when in the menstrual cycle is positive feedback occuring? what is the purpose of this positive feedback?

Answer 34

toward the end of the follicular phase | LH surge

Question 35

when can one be expected to observe a rise in basal body temperature?

Answer 35

commonly the day after ovulation

Question 36

what signals the demise of the corpus luteum?

Answer 36

low estrogen and progesterone levels

Question 37

what hormone promotes the differentiation of endometrial stromal cells into predecidual cells?

Answer 37

progesterone

Question 38

because of ovarian failure, individuals with Turner Syndrome have elevated serum concentrations of _____

Answer 38

FSH

Question 39

patient presents with hypogonadism and elevated levels of serum FSH, what is the diagnosis?

Answer 39

turner's

Question 40

a woman experiencing menopause would be expected to have _____ levels of FSH and LH? why? normal low high

Answer 40

no negative feedback