Female Reproductive Flashcards

Question

What is menopause and when does it happen?

Answer 1

* Menopause—cessation of menstrual cycles – Usually occurs between ages of 45 and 55 – Age of menopause has increased in last century – Menopouse considered complete when there has been no menstruation for a year

Answer 2

* Ovarian cycle—events in ovaries * Menstrual cycle—parallel changes in uterus

Answer 3

* Oogenesis—egg production – Produces haploid gametes by means of meiosis – Distinctly cyclic event that normally releases one egg each month – Accompanied by cyclic changes in hormone secretion – Cyclic changes in histological structure of the ovaries and uterus * Uterine changes result in monthly menstrual flow

Answer 4

development of the follicles around the egg that undergoes oogenesis

Answer 5

– Primordial follicles * Consists of a primary oocyte in early meiosis * Surrounded by a single layer of squamous follicular cells * Follicular cells connected to the oocyte by fine cytoplasmic processes for passage of nutrients and chemical signals * Concentrated in the cortex of the ovary – Primary follicles * Contain larger, secondary oocytes and a surrounding layer of cuboidal follicular cells – Secondary follicles * Oocytes are even larger and follicular cells now in two or more layers (granulosa cells) * Zona pellucida—layer of glycoprotein gel secreted by granulosa cells around the oocyte * Theca folliculi—connective tissue around the granulosa cells condenses to form a fibrous husk that differentiates into two layers – Theca externa: outer fibrous capsule rich in blood vessels – Theca interna: inner cellular, hormone-secreting layer producing androgens (androstenedione and testosterone), and granulosa cells convert them to estradiol – Tertiary follicles * As pools enlarge, they merge, forming a single antrum * Cumulus oophorus—a mound of granulosa cells on one side of the antrum that covers the oocyte and secures it to the follicular wall * Corona radiata—innermost layer of cells in the cumulus surrounding zona pellucida and oocyte – Forms a protective barrier around egg with function similar to blood–testis barrier – Mature follicles * About 20 days before ovulation, one follicle becomes dominant (the one destined to ovulate) – Remainder degenerate * It captures and holds FSH * At about 5 days before ovulation it is large enough to be considered a preovulatory (graafian) follicle

Answer 6

28 days, follicular, ovulation, luteal

Answer 7

hypothalamus - pituitary - ovaries - uterus

Answer 8

extends from beginning of menstruation until ovulation (Days 1-14) – Includes preovulatory phase: from end of menstruation until ovulation – Most variable part of cycle; seldom possible to predict date of ovulation – FSH stimulates follicles to grow and secrete estradiol – Dominant follicle becomes increasingly sensitive to FSH, LH, and estradiol

Answer 9

rupture of the mature follicle and release of its egg and attendant cells – Typically around day 14 * Estradiol stimulates a surge of LH and a lesser spike of FSH by anterior pituitary – LH induces several events * Primary oocyte completes meiosis I (producing secondary oocyte and first polar body) * Follicular fluid builds rapidly and follicle swells (resembles blister on ovary) * Macrophages and leukocytes secrete enzymes that weaken follicle wall * Nipple-like stigma appears on surface – Ovulation takes only 2 to 3 minutes * Stigma seeps follicular fluid for 1 to 2 minutes * Follicle bursts and remaining fluid oozes out carrying the secondary oocyte and cumulus oophorus * Normally swept up by ciliary current and taken into uterine tube

Answer 10

day 15 to day 28, from just after ovulation to onset of menstruation * If pregnancy does not occur, events happen as follows: – When follicle ruptures it collapses and bleeds into antrum – Clotted blood is slowly absorbed – Granulosa and theca interna cells multiply and fill antrum – Dense bed of capillaries grows amid them – Ovulated follicle has now become the corpus luteum * Named for yellow lipid that accumulates in theca interna cells, now called lutein cells – Transformation from ruptured follicle to corpus luteum is regulated by LH * LH stimulates corpus luteum to grow and secrete rising levels of estradiol and progesterone * 10-fold increase in progesterone is most important aspect of luteal phase – Progesterone has a crucial role in preparing the uterus for possibility of pregnancy – LH and FSH secretion declines over the rest of the cycle – High levels of estradiol and progesterone, along with inhibin from the corpus luteum, have a negative feedback effect on the pituitary – Corpus luteum begins process of involution (shrinkage) * Beginning about day 22 (8 days after ovulation) * By day 26 involution is complete and what was corpus luteum becomes corpus albicans—small scar * With diminishing ovarian steroid secretion, FSH levels rise, ripening a new cohort of follicles – Ovulation occurs in one ovary per cycle with the two ovaries usually alternating from month to month`

Answer 11

proliferative phase, secretory phase, premenstrual phase, and menstrual phase

Answer 12

rebuilding of functional layer of endometrium that was lost in last menstruation – At day 5 of menstruation, the endometrium is about 0.5 mm thick and consists only of basal layer – As new cohort of follicles develops, they secrete more estrogen – Estrogen stimulates mitosis in basal layer and regrowth of blood vessels to regenerate the functional layer – By day 14, endometrium is 2 to 3 mm thick – Estrogen also stimulates endometrial cells to produce progesterone receptors

Answer 13

endometrium thickens more in response to progesterone from corpus luteum – Day 15 to day 26 – Thickening due to secretion and fluid accumulation rather than mitosis – Endometrial glands secrete glycogen – Glands grow wider, longer, and more coiled – Endometrium 5 to 6 mm thick – Soft, wet, nutritious bed available for embryonic development

Answer 14

period of endometrial degeneration – Last 2 days of the cycle – Corpus luteum atrophies and progesterone levels fall – Triggers spasmodic contractions of spiral arteries – Causes endometrial ischemia (interrupted blood flow) – Brings about tissue necrosis and menstrual cramps – Pools of blood accumulate in the functional layer – Necrotic endometrium mixes with blood and serous fluid: menstrual fluid

Answer 15

discharge of menstrual fluid from the vagina * First day of discharge is day 1 of the new cycle * Average woman expels about 40 mL of blood and 35 mL of serous fluid over a 5-day period * Contains fibrinolysin so it does not clot

Female Reproductive Flashcards

(39 cards)