Final Exam, Female Reproduction Flashcards Preview

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Flashcards in Final Exam, Female Reproduction Deck (84):
1

Prenatal ovary

primordial gonocytes migrate and become oogonia which become primary oocytes after undergoing mitosis

2

Primary oocytes

diploid, 1-2 million
organize primordial follicle

3

Primordial follicle

oocyte and a single layer of flat, inactive follicle cells
have small metabolically inactive oocytes which can last from birth to menopause

4

Primary follicle

follicle cells form a single layer of cuboidal granulosa cells
oocyte enlarges dramatically

5

Oocyte activity in a primary follicle

produces RNA and proteins necessary for early embryogenesis
increases mitochonria
increases metabolic rate (at this point the follicle must continue to develop or the oocyte will die)

6

Secondary follicle

granulosa cells undergo mitosis to form multiple layers
secrete basement membrane and interstitial cells differentiate into theca interna and theca externa

7

theca interna

endocrine cells within the secondary follicle

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theca externa

connective tissue later surrounding a secondary follicle

9

Secondary follicles will undergo atresia without what hormone

FSH

10

atresia

the death of the follicle
programmed cell death

11

what is the fate of most secondary follicles

atresia

12

Tertiary follicles

aka antral follicle
develop only in the presence of adequate FSH
fillicular fluid builds up in an antrum, follicle enlarges

13

How many tertiary follicles will ovulate

1 in 5

14

In the tertiary follicle, FSH stimulates

granulosa cells to convert androgens to estrogens
aromatase

15

In the tertiary follicle, LH stimulates

androgen production by the theca interna
the androgens then pass through the basement membrane into the follicle

16

In the granulosa cells of the tertiary follicle, estrogens act as

autocrines causing increased:
granulosa cell mitosis
FSH receptors
Estrogen receptors
estrogen production
increased IGF's

17

Follicular Fluid

secreted by granulosa cells
specialized environment for oocyte and granulosa cells
similar to serum but has many hormones, cytokines, extracellular matrix molecules, and binding proteins

18

dominant follicle

the follicle that will ovulate

19

the composition of follicular fluid plays a role in the selection of

the dominant follicle

20

During the 28 day reproductive cycle, estrogen secretion by the dominant follicle

rises steadily

21

The estrogen found in a woman's blood during the follicular phase of their cycle is from

the follicles that will ovulate
can predict how many follicles will ovulate by measuring the amount of estrogen in her blood the day before ovulation

22

Immature follicles undergo atresia due to

lack of the right ratio of FSH and LH at critical times
granulosa cells not providing correst signals to the oocyte
oocyte not prodiving correct signals to the granulosa
inappropriate paracrine signals between the granulosa and theca interna

23

What can "rescue" preovulatory follicles that would otherwise become atretic

FSH- routinely used in fertility clinics to enhance follicular development

24

Functions of granulosa cells

Nurse cells for the oocyte
blood-follicle barrier
steroidogenesis
production of protein hormones
role in ovulation
undergo luteinization

25

Cumulous oophorous

granulosa with the closest contact with the oocyte
have cytoplasmic extensions into the oocyte
can pass second messengers directly into the cell

26

Granulosa cells convert testosterone

to estrogen
secrete progesterone when mature in response to FSH and LH

27

Inhibin

produced by granulosa cells
negative feedback control of FSH secretion

28

Mullerian inhibiting hormone

produced by granulosa cells
after the mullerian tracts have already develped, inhibits oocyte development

29

Relaxin

produced by granulosa cells
involved in parturition, ovulation
causes breakdown of connective tissue

30

oxytocin

when produced by granulosa cells
local effects on oviduct motility

31

Cytokines produced by the granulosa cells

regulate their own development as well as functions of the theca

32

Luteinization

granulosa cells differentiate into luteal cells of the corpus luteum after ovulation

33

Theca Interna cells

similar to leydig cells
respond only to LH

34

In theca interna cells, LH triggers

cholesterol side chain cleavage via cAMP

35

functions of theca interna cells

produce androgens and estrogens
secrete about 20% of circulating androgens

36

theca interna cells differentiate into

luteal cells of the corpus luteum and produce progesterone and other hormones

37

Ovulation is triggered by a rise in

LH

38

Effect of LH on granulosa cells

produce/secrete progesterone
stop inhibiting oocytes meiosis
secrete histamine, serotonin, and bradykinin
prostaglandin F2alpha

39

Function of the corpus luteum

produces progesterone, estrogen, and numerous protein hormones that prepare the body for pregnancy

40

How long does the corpus luteum (CL) survive when pregnancy is not achieved

21 days

41

CL is dependent on which hormone for survival

LH

42

luteolysis

LH levels decline causing regression of the CL

43

After luteolysis, the CL becomes a

corpus albicans

44

human Chorionic Gonadotropin

used for pregnancy tests
has a similar structure to LH and binds to LH receptors on the CL causing it to grow and increase steroidogenic activity

45

The corpus luteum regresses during the second trimester and is rejuvenated by

prolactin at the end of pregnancy

46

Phases of the ovarian cycles

follicular phase
luteal phase

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follicular phase of the ovarian cycle

first half of the ovarian cycle
when follicles are developing

48

major hormone secreted during the follicular phase

estrogen, rises during this phase
(very little progesterone)

49

Luteal phase of the ovarian cycle

second half of the ovarian cycle

50

major hormones produced during the first half of the luteal phase of the ovarian cycle

estrogen and rising progesterone

51

major hormones produced during the second half of the luteal phase of the ovarian cycle

falling estrogen and progesterone

52

Granulosa cells of the tertiary follicles secrete

inhibin
estrogen

53

initial low levels of estrogen secreted by the granulosa cells exert

negative feedback on the tonic center of the hypothalamus leading to decreased GnRH secretion leading to decreased LH secretion

54

Rising levels of inhibin secreted by the granulosa cells leads to

negative feedback at the anterior pit. to suppress FSH secretion in response to GnRH

55

estrogen exerts positive feedback on what are of the hypothalamus

the cyclic center to trigger a large release of GnRH

56

preovulatory surge of FSH & LH

induced after a large surge of GnRH

57

preovulatory surge of LH

causes ovulation and CL formation

58

preovulatory surge of FSH

stimulates development of follicles for future cycles

59

Progesterone exerts negative feedback on which neurons

GnRH, suppressing their ability to respond to the actions of estrogen

60

The CL secretes inhibin during what phase of the ovarian cycle

luteal phase
suppressed FSH and follicular development during the luteal phase

61

Estrogen

feminizes the body, opposes androgen action
favors glycogen and fat storage
positive mood effects

62

progesterone

prepares the uterus to allow embryo survival and implantation
stimulates the uterus to secrete proteins that nourish
stimulates glandular development in breasts

63

Hormone levels just prior to ovulation

high estrogen and testosterone

64

hormone levels just prior to menstruation

high testosterone and low estrogen

65

testosterone and androstenedione

20-40% of circulating androgens come from ovary
two peaks of production from the ovary

66

Proliferative phase of the uterus

Rising Estrogen stimulates the proliferation of the uterine endometrium proliferation of stromal connective tissue, increased collagen deposits growth of glandular ducts, increase in blood supply to the endometrium

67

secretory phase of the uterus

Progesterone stimulates uterine glandular development into thick coiled structures with a lumen filled with secretory material = nourishment for pre implantation embryo; development of spiral arteries = increased surface area

68

Results of luteolysis in the uterus

Progesterone and Estrogen withdrawal → constriction of the spiral arteries → decreased blood flow to the endometrium → death of lumenal layers of endometrial cells, invasion by lymphocytes → menstruation = loss of dead endometrial cells and blood

69

In the oviducts, estrogen enhances

motility of the cilia favoring the creation of waves of peritoneal fluid that help draw the oocyte into the oviduct

70

cervical muscous during the follicular phase

estrogen creates thin watery mucous
volume and consistency increases in the preovulatory stage

71

cervical mucous just prior to ovulation

stringy, crystallizing of mucous creates channels for the sperm to swim through

72

cervical mucous during the luteal phase

progesterone leads to thicker mucous that blocks the penetration of both sperm and foreign organisms

73

effect of low estrogen on the immune system

stimulates interleukin 1 production

74

effect of high estrogen on the immune system

inhibits IL-1 secretion

75

Effect of low levels of progesterone on the immune system

as with the menstrual cycle
stimulates IL-1 synthesis

76

Effect of high levels of progesterone on the immune system

as with pregnancy
inhibits IL-1 synthesis
important for immune tolerance of the mother to the fetus

77

human Chorionic Gonadotropin

glycoprotein similar to LH but has a longer half life
produced by trophoblast cells of the developing embryo as early as day 7

78

hCG stimulates the placenta to convert cholesterol to

progesterone

79

Estrogen production during pregnancy requires

the production of DHEA (dehydroepiandrosterone) a weak androgen

80

DHEA is synthesized by

the fetal zone of the fetal adreal

81

Actions of estrogen during pregnancy

Growth of uterus, stimulates growth, increased strength and contractions of the uterine
muscle layer; growth of the vaginal canal, relaxation of the pelvic ligaments;
growth of the duct system of the mammary glands
effects on GI tract thought responsible for morning sickness
stimulates fat deposition, glycogen storage, salt and water retention

82

actions of progesterone during prenancy

uterine decidual cell formation (embryo nutrition)
suppresses coordinated uterine contractions by inhibiting the formation of gap junctions
between myometrial cells
stimulates glandular development in the mammary glands
inhibits the actual synthesis of milk during pregnancy

83

placental prolactin

promotes development of the mammary glands for milk synthesis:
Production of enzymes during pregnancy – but milk synthesis itself is inhibited by high progesterone levels.
Placental Prolactin promotes fetal adrenal maturation

84

placental lactogen

aka human chorionic somatomammotropin
separate hormone from Prolactin. Has Growth Hormone actions in human, and lactogenic actions only in nonprimates. Stimulates protein synthesis, causes insulin insensitivity in mother → higher blood glucose in pregnant women,→ more glucose available to the fetus
Stimulates use of fatty acids for mother's energy needs towards end of pregnancy