3 ovulation Flashcards
what controls sexual cycles?
hypothalamus
what is the role of GnRH in sexual cycles?
GnRH acts on cells of the anterior lobe of the pitiutary gland which secrete gonadotropins
whats the role of GSH and LH in the ovary?
GSH and LH stimulate and control cyclic changes in the ovary
At the beginning of each ovarian cycle ____________ are stimulated to grow under the influence of FSH
15 to 20 primary-stage (preantral) follicles
At the beginning of each ovarian cycle 15 to 20 primary-stage (preantral) follicles are stimulated to grow under the influence of ___
FSH
____________15 to 20 primary-stage (preantral) follicles are stimulated to grow under the influence of FSH
At the beginning of each ovarian cycle
what happens to the follicles that dont reach maturity?
degenerate and become atretic and replaced by connective tissue forming corpus atreticum
Proliferation of the granulosa is mediated by ……
growth differentiation factor 9, a member of the transforming growth factor beta
Theca interna and granulosa cells produce ______: theca interna cells produce androstenedione and testosterone, and granular cells convert these hormones to estrone and 17-beta estradiol
estrogens
Theca interna and granulosa cells produce estrogens: ….., and granular cells convert these hormones to estrone and 17-beta estradiol
theca interna cells produce androstenedione and testosterone
Theca interna and granulosa cells produce estrogens: theca interna cells produce androstenedione and testosterone, and granular cells ….
convert these hormones to estrone and 17-beta estradiol
what three things happen after the theca interna and granulosa cells produce estrogens?
Uterine endometrium enters the proliferative phase
Thinning of the cervical mucus to allow passage of sperm
Feedback to anterior lobe of the pituatary to secrete LH
Midcycle there is an ________ that elevates concentrations of maturation-promoting factor, causing oocytes to complete meiosis I and initiate meisosis II
LH surge
Midcycle there is an LH surge that ….., causing oocytes to complete meiosis I and initiate meisosis II
elevates concentrations of maturation-promoting factor
Midcycle there is an LH surge that elevates concentrations of maturation-promoting factor, causing ….
oocytes to complete meiosis I and initiate meisosis II
what does the LH surge mid cycle stimulate?
This surge stimulates production of progesterone by follicular stromal cells (leutinization) and causes follicular rupture and ovulation
What are the steps of the ovarian cycle? ( until what happens if secondary oocyte is not fertilized)
what also increases in reposnse to LH surge?
Prostaglandins also increase in response to LH surge which will cause muscular contractions in the ovarian wall
what also increases in reposnse to LH surge?
Prostaglandins also increase in response to LH surge which will cause muscular contractions in the ovarian wall
what do the muscular contractions in the ovarian wall do?
squeeze the oocyte along with its granulosa cells from the region of cumulus oophurus
what happens to the granulosa cells and cells of the theca interna after ovulation?
After ovulation granulosa cells in the wall of the ruptured follicle and the cells of theca interna are vascularized by surrounding vessels
Estrogen and progesterone secretions cause ….
uterine mucose to enter progestational phase in preparation for implantation
what carries the oocyte into the uterine tube?
sweeping motions of the fimbrae and by the cilia on the epithelial lining
what happens to the cumulus cells once the oocyte is in the tube?
withdraw their cytoplasmic processes from the zona pellucida and lose contact with the oocyte
what happens to the cumulus cells once the oocyte is in the tube?
withdraw their cytoplasmic processes from the zona pellucida and lose contact with the oocyte
when does the fertilized oocyte reach the uterine lumen?
in approximately 3 to 4 days
what happens to the corpus luteum if fertilization doesnt occur?
the corpus luteum reaches maximum development approximately 9 days post-ovulation and shrinks to form a mass of fibrotic scar tissue, corpus albicans
what happens to progestrone production if fertilization doesnt occur?
Progesterone production decreases and menstrual bleeding begins
what happens to the corpus luteum if fertilization does occur?
If fertilizationoccurs degeneration of corpus luteum is prevented by human chorionic gonadotropin (hCG) hormone secreted by the syncytiotrophoblast of the developing embryo
what is fertilization?
The process by which male and female gametes fuse and usually occurs in the ampullary region of the uterine tube
Movement of sperm from the cervix to the uterine tube occurs by __________ __ ___________-from thirty minutes to 3 days
muscular contractions of the uterus and uterine tube
Movement of sperm from the cervix to the uterine tube occurs by muscular contractions of the uterus and uterine tube-from …
thirty minutes to 3 days
