Menstrual Cycle

Question 1

The menstrual cycle is defined as a series of changes controlled by hormones from the _____ gland and _____ that help prepare the female ____ for possible pregnancy

Answer 1

Pituitary gland, ovaries, uterus

Question 2

The first day of menstruation is considered Day ___ and Day ___ of the cycle.

Answer 2

28 and 1

Question 3

How many stages are there in the menstrual cycle? What are they?

Answer 3

4

Follicular/proliferative stage, Ovulation, Secretory/Luteal phase, Menstruation

Question 4

During the follicular/proliferative phase, the _____ produces FSH causing follicles (egg cell capsules) to form/mature. As the follicle grows, its cells produce ______ in increasing amounts.

Answer 4

pituitary

estrogen

Question 5

Estrogen has (negative/positive) feedback on the pituitary FSH production.

Answer 5

Negative

Question 6

_____ causes the uterine lining (endometrium) to grow thicker

Answer 6

Estrogen

Question 7

Pituitary FSH causes several follicles in each ovary to mature at once, however, only 1 (typically) becomes the _____ follicle and ovulates

Answer 7

dominant

Question 8

If >1 dominant follicle occurs, what can result?

Answer 8

Twins!

Question 9

Ovarian follicles have several types of cells, what are they? Describe them.

Answer 9

Granulosa cells: several-cells-thick layer surrounding the egg and fluid around it

Cumulus cells: specialized layer of granulosa cells directly surrounding egg

Theca Cells: 2 thick layers of cells that surround the granulosa cells, outside of their basal lamina

Question 10

____ and ____ cells make estrogen when stimulated by FSH to grow/divide

Answer 10

Theca and Granulosa

Question 11

Once a follicle is clearly dominant, other follicles become _____ and _____

Answer 11

atretic and shrink

Question 12

Typically, a dominant follicle must grow to at least _____ cm in diameter to ovulate

Answer 12

2.5 cm

Question 13

All maturing follicles are secreting ______

Answer 13

estrogen (causes thickening of uterine lining)

Question 14

During the follicular phase, estrogen is (inhibitory/stimulatory) to FSH and (inhibitory/stimulatory) to LH –> (negative/positive) feedback

Answer 14

Inhibitory; stimulatory

Positive feedback

Question 15

Increased estrogen from the dominant follicle stimulates the ______ gland to produce _____; as Estrogen climbs rapidly, the dominant follicle gets big, and ____ production suddenly spikes/surges.

Answer 15

pituitary; LH; LH

Question 16

What is the direct cause of ovulation?

Answer 16

LH surge

Question 17

During ovulation, _____ potentiates GnRH and _____ inhibits FSH

Answer 17

Activin; Inhibin

Question 18

Activin is made by ______ in the ______ phase and stimulates pituitary production of _____ –> (negative/positive) feedback

Answer 18

follicles; follicular; FSH; positive

Question 19

Inhibin A: made in ______ phase, peaks at _______

Inhibin B: made in ______ phase and does a lot to inhibit _____

Answer 19

Follicular; ovulation

Luteal; FSH

Question 20

During the Secretory/Luteal phase, the ruptured follicle heals inside the ovary, forming the _______ _______

Answer 20

corpus luteum (“yellow body”)

Question 21

The corpus luteum produces _______

Answer 21

progesterone

Question 22

The corpus luteum is necessary until _____ wks when the placenta is is making sufficient estrogen and progesterone

Answer 22

~8-11 wks

Question 23

What does the estrogen/progesterone combo maintain during the secretory/luteal phase?

Answer 23

The added growth of uterine lining

Question 24

If an ovulated egg is fertilized and a blastocyst implants,

_____ and _____ stabilize the corpus luteum and prevent it from decomposing, which maintains ______ levels

Answer 24

HCG and LH; progesterone

Question 25

An embryo in the uterus will secrete _____

Answer 25

HCG

Question 26

HCG mimics _____, maintaining the uterine lining just like ____ does

Answer 26

LH

Question 27

The endometrium is not shed when _____ is present

Answer 27

HCG

Question 28

What is the chemical that is detected by pregnancy tests?

Answer 28

HCG

Question 29

If there is no blastocyst implantation, what occurs?

Answer 29

Menstruation

Question 30

LH levels gradually (decrease/increase) after the LH surge

Answer 30

Decrease

Question 31

On what day during the menstrual cycle does ovulation usually occur?

Answer 31

day 14

Question 32

If embryo is not implanted by 14 days after ovulation, what will happen to the corpus luteum? Estrogen and progesterone levels?

Answer 32

corpus luteum decomposes | estrogen and progesterone levels decrease

Question 33

With no progesterone to maintain the uterine lining, the _______ is shed and moves out through the vagina

Answer 33

endometrium

Question 34

What is the hormonal event that is the direct trigger for menses to begin?

Answer 34

decrease in estrogen and PROGESTERONE levels

Question 35

What is the structure that disintegrates in menses?

Answer 35

Corpus luteum, which leads to decrease in progesterone, which leads to endometrial shedding

Question 36

What is the ovarian event that created the corpus luteum/endometrium?

Answer 36

Ovulation

Question 37

What is the hormonal event that triggered the maturation of the ovarian follicles?

Answer 37

LH surge

Question 38

What are FSH and LH levels typically like on the first day of a woman's period?

Answer 38

Low

Question 39

Are estrogen and progesterone levels high or low on the first day of menstruation?

Answer 39

Low

Question 40

OCPs (decrease/increase) the hypothalamic release of GnRH and (decrease/increase) the pituitary release of LH and FSH

Answer 40

decrease; decrease (negative feedback!)

Question 41

If a woman is taking an OCP and becomes pregnant, will she still have a period? Explain.

Answer 41

No; HCG from pregnancy prevent endometrial shedding, uterine lining will grow with estrogen, and she will not have a period

Question 42

What are the effects of the decrease of pulsatile GnRH and decrease of LH on the ovaries?

Answer 42

No maturation of the follicles, no dominant follicle, no LH surge, no ovulation

Question 43

What is happening to the uterus while a woman is taking a daily OCP?

Answer 43

The uterine lining will thicken due to progesterone