Endocrine 3: Female Reproductive System Flashcards
the ___,___ and ___ undergo periodic cyclic changes (structural and functional) from puberty to menopause
uterus, uterine tubes, ovaries
____ is the initiation of the menstrual cycle
menarche
the menstrual cycle averages about ___ days
28-30
during ____, the ovaries cease their reproductive and endocrine functions
menopause
menopause typically occurs between the ages of ___
45-50
when does menarche occur? (age)
9-12
what are the 2 main stages of the menstrual cycle?
follicular and luteal
what happens on day 1 of the menstrual cycle?
bleeding begins
what happens on days 1-7 of menstrual cycle?
multiple follicles develop and on day 7 the dominant one is selected
what happens between days 7-14 of the menstraul cycle?
dominant follicle develops and on day 14 ovulation
what happens between days 14-25 of the menstrual cycle?
the corpus lute functions
what happens between days 25-28 of the menstrual cycle?
the corpus luteum degenerates
the follicular phase is from days ____ to ___
1-14
the luteal phase is from days ___ to ___
14-28
____ are paired, plum-shaped white organs about 3cm long, 1.5 cm wide and 1cm thick
ovaries
what are the 2 different regions of the ovaries?
medulla and cortex
the medulla of the ovary is located in the ___ portion of the ovary, it contains ____ tissue with ___ and ___ vessels and ____
central; loose connective; blood and lymph vessels and nerves
the cortex of the ovary is located in the ____ portion of the ovary, and contains ____ embedded in ___tissues
outer; ovarian follicles; connective
is there a distinct boundary between the ovarian cortex and medulla?
no
what are the 2 functions or the ovaries?
- development and production of games oocytes
2. synthesis and secretion steroid hormones
what are 2 steroid hormones secreted by the ovaries?
estrogen and progesterone
what is the role of estrogen?
responsible for growth and maturation of sex organs, mammary gland and sex characteristics
what is the role of progesterone?
prepares internal sex organs for pregnancy and mamary gland for lactation
lactation is also called
alveolar proliferation
the structural and functional changes associated with menstrual cycle are controlled through a neurohormonal mechanism called the ______
hypothalamic pituitary gonadla axis
does the HPGA act as a single or multiple entities?
single
FSH stimulates the _____in the ovary before the release of an egg in ovulation, and also increases the production ___
growth of follicles; oestradiol
LH stimulates ovaries to produces ___
oestradiol
what is the function of oestradiol? (2)
causes release of egg during ovulation and stimulates the corpus luteum to make progesterone in case os fertilization
what are the 2 parts of the follicle?
egg surrounded by steroidogenic cells
what are the 2 types of steroidogenic cells in the follicle?
granulosa and theca cells
after ovulation, the oocyte remains viable for only ____hrs
24
what happens to the secondary oocyte if fertilization does not occur?
degenerates and passes through the uterine tube
what are the 3 main phases of follicle development?
- primordial follicles
- growing follicles
- mature follicles
primordial follicles consist of
oocyte surrounded by single layer of flat follicle cells
growing follicles are divided into what 3 categories?
- primary follicle
- preantral follicle
- early antral follicle
in the primary follicle ____hormone causes the oocyte to enlarge and follicle cells divide to form a ___primary follicle. between the oocyte and follicle cells there is a thick extracellular glycoprotein layer called the ___
FSH; unilamilar; zona pellucida
in the preantral phase, the granulose cells ___ to form ___, while the stromal cells differentiate into ___ known as ___
further divide; multiple layers ; sheet of connective tissue; early theca cells
in the early antral phase, both the theca and the granuloza cells ___ and within the cell layers, a fluid-filled space develops called the ___
proliferate; antrum
the oocyte is connected to the surrounding cell layers by the ___
cumulus oophorous
a mature follicle is also called a ___
Graafian follicle
the making of a mature follicle is driven by ____ and ___stimulation
FSH and LH
most follicles degenerate through ___
atresia
by the beginning of reproductive lifespan, about ____oocytes are in the ovary, but only about ___ will ovulate
400 000, 450
the mechanism for choosing the dominant follicle follows the ___ model of the ovary
two-gonadotropin
explain the two cell/two gonadotropin theory of follicle development
estrogen is produced in the granulose cells by aromatization of androgens in the theca cells; this is catalyzed by aromatase which is enhanced by FSH stimulation of specific receptor of these cells
a combination of ___ and ___ effects is responsible for the release of oocyte in the middle of the menstrual cycle
hormonal and enzymatic
what are the 3 follicular phases?
early, late, luteal
when do LH and FSH spike?
during ovulation to push egg out
when do estrogen and inhibin spike?
during ovulation and middle of luteal phase
when does progesterone spike?
during luteal phase
during the early follicle stage, FSH ____in response to removal of negative feedback by ____ and ____ following the loss of the corpus luteum at the end of the previous cycle
increases; estrogen and progesterone
the rise of FSH in the early folicle stage promotes the development of follicles whose ___ cells will secrete ___
granulosa; estrogen
estrogen has ___ effects on the hypothalamus and pituitary, so when the follicles release it, it causes the FSH secretion to ___
negative; drop
estrogen stimulates the expression of ____ receptors, making granulose cells more receptive to it
FSH
during what follicle phase is the dominant follicle chosen?
late
the dominant follicle produces large amounts of ___ and small amounts of ___
estrogen; progesterone
the rapid rise in estrogen with some progesterone caused by the dominant follicle results in the positive feedback effect on the secretion of ____ and ___
GnRH and LH
high levels of LH triggered in the late follicle phase is what induces ___ by ___
ovulation by weakening the follicle wall, causing the egg to burst through
the early to mid stages of the luteal phase is characterized by differentiation of granuloza and theca into the ____ which sectretes some ___ and large amounts of___
corpus luteum (yellow body); estrogen; progesterone
the luteal phase is characterized by low levels of __ and __, resulting from the negative feedback effects of ___a dn __
FSH and LH. estrogen and progesterone
at the end of the luteal phase w/o pregnancy, the corpus luteum ___ and ____ causes mentrual bleeding and a rise in ___ and___ hormones
degenerates; loss of steroid hormone production; LH ad FSH
a fertilized egg takes several days to transit to the Fallopian tube, during which the ____ of the corpus luteum prepare the uterine wall for implantation of the blastocyst
hormonal secretions
after the release of the ovum, the remaining follicles true into __ which produce ___ and prepares for pregnancy
corpus luteum; progesterone
in preparation for blastocyst implantation, the epithelial cells begin to store __
glycogen
pregnancy lasts about ___ days
280
pregnancy is counted from the ___ day of the last menstrual cycle
first
the first sign of pregnancy is often ___
amenorrhea (loss of period)
what hormone is used in pregnancy tests?
positive result for human chorionic gonadotropin (hCG), a glycoprotein produced by syncytiotrophoblast
pregnancy tests can recognize pregnancy within ___ days after fertilization
7-8
hCG levels ____ every 2 days in early pregnancy and then declines when the ____ unit takes over steroid production
doubles; feta-placental
driven by ___, ___, ___, and ___, ,the mammary glands undergo several changes needed for lactation
estrogen, progesterone, prolactin, placental lactogen
prolactin induces ___ and oxytocin promotes __
milk production; milk ejection
the hypothalamus secretes ___ to the ____ pituitary to produce prolactin
prolactin releasing hormone, anterior
the hypothalamus uses the ___ to secrete oxytocin form the ___ pituitary
paraventricular nucleus; posterior
PTH related peptide is released by breast ___ cells
epithelia
PTHrP secretion is controlled by ___, ___ and a ___ receptor
sucking, prolactin, ca
what is the effect of PTHrP on bone resorption and release of Ca and PO4 in the breastmilk?
increases both
