Home > Flashcards > Women's & Gender Studies > Menstrual Cycle

Details Title: Menstrual Cycle Description: 4.17.07 Total Flash Cards: 33 Created: 04/17/2007 17:57:15	To study from this set of flash cards, or to create your own your own study flash cards, register HERE. If you are already a registered user, CLICK HERE.
Cards Term Where is GnRh produced? Definition in the arcuate nucleus of the hypothal. Term What is special about GnRH? Definition it is small enough (it's a decapeptide) that it can cross through BBB Term Where are FSH and LH produced? Definition in the anterior pituitary Term Here is E2 made? Definition in the follicle of the ovary Term Wher eis P4 made? Definition in the CL of the O Term What is a follicle? Definition Oocyte (egg) surrounded by 1 or more layers of specialized cells theca cells and granulosa cells Term when does the follicle burst? Definition Oocyte persists in prophase of the 1st mieotic until the midcycle LH surge and ovulation Term What are thecal cells Definition surround granulosa cells. have LH receptors Term What kind of receptors do Theca Cells have? Definition LH receptors Term What are granulosa cells? Definition inner layer of cells around oocyte. Have FSH receptors Term What type of receptors do Granulosa cells have? Definition FSH Term What is estrodiol's main function? Definition GLOBAL FUNCTION. Negative feedback mainly at Pituitary in humans. Estradiol suppresses FSH release physiologically. Term What is its local function? Definition Positive feedback mainly at the pituitary in humans. High levels of estradiol stimulate release of LH from pituitary and LH begins process of ovulation . This leads to follicular dominance. Term What do theca cells produce? Definition C-19 steroid, androgen, Androstenedione Term What do Granulosa cells produce? Definition C-18 steroid, estrogen, Estradiol Term Where does GnRH travel from/to? Definition Portal circulation from hypothalamus to anterior pituitary Term How is GnRh modulated? Definition Pulsatile; Permissive but pulse frequency and amplitude does change over the menstrual cycle and during a women’s life Term What does LH do? Definition LH Luteinizing Hormone: stimulates steroid synthesis in the ovary Term What does FSH do? Definition FSH Follicle Stimulating Hormone: stimulates growth of follicles Term Where are FSH receptors? Definition on the GCells Term What does FSH do? Definition at the Primary follicle stage FSH receptors form on the granulosa cells, this is the layer of cells closest to the ooycte (egg) A whole cohort of primary follicles is stimulated (recruitment) Term What do GCs do? Definition Granulosa cells aromatize androstenedione (C-19) to estradiol (C-18) Term How are GCs, FSH, and E2 related? Definition (FSH stimulates aromitazing enzyme synthesis), and estradiol (E2) increases FSH receptors Term How long is an oocyte in prophase? Definition Oocyte remains arrested in prophase of the 1st meiotic division but as the follicle grows the oocyte acquires the capacity to complete the 1st meiotic division Term Where are LH receptors? Definition theca cells Term What does LH do? Definition LH stimulates steroid biosynthesis, conversion of the C-27 cholesterol into the C-19 androgen (side chain cleavage), androstenedione. AND, Graffian follicle, preovulatory dominant follicle LH release (positive feedback from E2) Initiates continuation of meiosis Luteinization of granulosa cells Prostoglandin synthesis for digestion of the follicular wall Term What do FSH, LH, HCG, and TSH all have in common? Definition all glycopeptide dimers, too big to go through BBB (unlike GnRH) Term What is FSH's structure? Definition FSH large complex glyco-protein hormone consisting of 2 chains, alpha and beta Term What is LH's structure? Definition LH large complex glyco-protein hormone consisting of 2 chains, alpha and beta , similar in structure to HCG, beta chain longer and more carbohydrate, LH has short half life, pulsatile Term What is LH similar in structure to? Definition LH, but beta chain longer and more carbohydrate, LH has short half life, pulsatile Term What does the corpus luteum do? Definition Secretes Progesterone Pro_Gestation! Prepares the endometrium for implantation; Changes the endometrium from proliferative (cell division) to secretory Term How long is CL's half life? Definition Has a fixed life time of approximately 14 days unless HCG is present (HCG is a long acting LH) Term What is menstruation? Definition Progesterone withdrawl; Proliferation (cell division) caused by “unopposed” estrogen”; Secretory caused by progesterone for implantation; Menses- Withdrawal bleed