Female Reproductive Sys Flashcards
Hormonal Control
pulsatile release of GnRH to start puberty
All follicles in ovarian cortex prior to that are primordial follicles
Relase of LH & FSH from basophils of ant pituitary
Hormonal Control
Ovary
Cortex- various ovarian follicle stages, corpus luteum & corpus albicans
Medulla- loose CT, BV, lymphatic vessels, n. fibers
Germinal epithelium- modified peritoneum, covers ovary from mesothelium & composed of simple cuboidal cells
Tunica albuginea- dense CT beneath germinal epithelium
Ovarian Cortex
Stroma w/ stromal cells & ovarian follicles
Primordial germ cells (oogonia) are from yolk sac endoderm & migrate to developing goand in 6th week.
Undergo mitosis until near end of 5th month- 5 to 7 mill oogonia
Only 1 mill oogonia will be surrounded by follicular cells & survive to time of birth.
Remaining oogonia atrophy
Cycle continued
Oogonia that survive enter prophase I & known as primary oocyte
Meiosis is arrested in diplotene stage of meiosis I by OMI produced by follicular cells.
Total of 450 ooocytes released over the entire reproductive years
All other follicles degen & die.
Different Stages of Follicle/Oocyte
FSH Indep
Primordial Follicles (non growing)
Primary/prenatral follicles (growing)
FSH dep
Secondary/antral follicles (growing)
Mature or Graafian follicles (preovulatory) (growing)
Ea follicle contains primary oocyte surrounded by 1 or multilayer follicular or granulosa cells
Secondary oocyte formed before ovulation when the oocyte completes first meiotic division
Primordial Follicle
Smallest & most numerous type of follicles in cortex of ovary.
Ea is composed of 1 layer of flat follicular cells around primary oocyte separated from stroma by basement mem
Primary oocyte arrested in prophase I - 1 nucleus, Golgi, RER, mitoch, lysosomes
Primary Follicles
Oocyte grows
- unilaminar primary follicle- primary surrounded by simple cuboidal or columnar follicular cells single layer
- multilaminar primary follicle- follicular cells prolif & stratify, & now are granulosa cells. Prolif of follicular cells is due to activin produced by primary oocyte
Multilaminar Primary Follicle
Zona Pellucida
during primary follicle stage, an amorphous substance appears, separating oocyte from follicular cells.
Contains ZP1, 2, 3 secreted by oocyte & form extracell coat of glycoprotein
ZP-3 is most important, acts as R for sperm binding & for inducing acrosomal rxn
Theca interna, theca externa, granulosa cells
Stromal cells around multilaminar primary follicle (theca folliculi) form inner theca interna (richly vascular layer) & outer theca externa (fibrous CT)
Theca interna cells: steroid producing cells, possess LH R on cell mem & influenced by LH.
Produce androstenedione (male sex hormone), which enters granulosa cells where converted to estradiol by aromatase.
Granulosa cells & theca interna are seprated by thickened basal lamina
Secondary/Antral Follicles
Characterized by accumulations of fluid known as liquor folliculi among granulosa cells
Prolif of granulosa cells depends on FSH, & possess FSH R.
FSH & estrogen induce granulosa cells to express LH R
Primary oocyte bigger but no further growth due to OMI!
Liquor folliculi- exudate of plasma, w/ GAGs, proteoglycans, steroid binding proteins & hormone (estradiol, inhibin, activin)
Follicle
most of follicles reach this stage undergo atresia
Some granulosa cells associate w/ atretic follicles form interstitial glands which secrete estrogen until menopause
Few secondary follicles continue to develop into mature follicles
Light pink= collapsed ZP
Dark pink= BV
Mature Graafian Follicle
Droplets of liquor folliculi coalesce to form single fluid filled chamber called antrum.
Granulosa cells rearrange & primary oocyte is surrounded by small group of granulosa cells called cumulus oophorus
Single layer of granulosa cells that immediately surrounds primary oocyte is called corona radiata
Cell structure
continued formation of liquor folliculi causes cumulus oophorus composed of primary oocyte, corona radiata & associated follicular cells to detach from its base & float freely w/in liquor folliculi.
Secondary oocyte is fomred shortly before ovulation when oocyte completes first meiotic division
Corpus Luteum
Formed from Graafian follicle that ovulated
Clot removed by phagocytes, high LH levels change structure
F as temporary endocrine gland & supports uterine endometirum
Cell Model
Progesterone always exert - feedback
Lutein Cells
Granulosa lutein- 80% of corpus luteum, pale staining steroid producing cells, produce mainly progesterone & estrogen
Theca lutein- 20% corups luteum, dark staining, secrete androgens & minor progestrone amts
Fate of Corpus Luteum
If pregnancy occurs- hCG from placenta maintains corpus luteum for 3 months.
Now its corpus luteum of pregancne & secreted hormones.
Intro of PG could cause degen of corpus luteum & abortion of fetus.
Placenta eventually takes over progesterone production & corpus luteum degrades into corpus albicans w/o fetus loss
If no pregnancy- corpus luteum stops secreting progesterone & decays. Degen to corpus albicans.
Atretic Follicles
Follicles that undergo degeneration
Of all follicles present in ovaries @ menarche, only 0.1-0.2% develop to maturity & undergo ovulation.
Ovarian medulla
richly vascular fibroelastic CT
Hilar cells (like Leydig, secrete androgens)
Uterine Tubes
oviducts, fallopian tubues
infundibulum, ampulla, isthmus & intramural portions
Fertilization usually happens in ampulla & reconstittues diplodi number of chrom
Obiduct F
- receive ovum from ovary
- usual site of fertilization of ovum (ampulla)
- provide nourishment for fertilized ovum
- transports fertilized ovum to uterine cavity
Mucosa in Oviduct Walls
simple columnar epith & underlying lamina propria
- ciliated- cilia beat towards uterus, causing viscous liquid film movement
- non ciliated- Peg cells, viscous liquid in lumen of oviduct consists mainly products of secretory cells. Secretions proteict & supply nutrients to fertilized oocyte. Also promote capacitation.
Muscularis in oviduct
2 layer smooth m. (inner circ, outer long)
Conractions of muscularis of oviduct together w/ movement of liquid film in its lumen tranport ooctye or conceptus towards uterus.
Serosa
**fallopian tube is intraperitoneal **
Body & fundus of uterus
outer layer: perimetrium
fundus covered by seros & body surrounded by adventitia
mid layer: myometrium
forms bulk of uterine wall, bundles of smooth m. fibers separated by CT. Forms 3-4 poorly defined layers. Size & number of m. cells related to estrogen levels. During prog myometrium grows by both hypertrophy & hyperplasia. Diminish in menopause.
Body & fundus of uterus 2
inner layer: endometrium
mucosal lining of uterus
Normal implantation site
Simple columnar epith (ciliated & secretory/ non PeG cells) b/t menarche & menopause
Lamina propria presents which invests branched tubular glands that extend to myometrium. Structure of glands varies according to phase of menstrual cycle.
- stratum basale- retained @ menstruation & responsible for regen of endometrium
- stratum functionale- sloughed off @ menstruation
Menstrual Cycle
Day 1-4 menses, desquamation
Day 5-14 proliferative/follicular- re epith of lining & renewal
Day 15-28 secretory/luteal- thickening of endometrium as result of edema & accumulated glycogen secretions of highly coiled endometrial glands
Menstrual Cycle
Glands
Myometrium @ different stages
Pregnant Endometrium/Decidua
if implantation occurs, embryonic trophoblast cells produce hCG which stim corpus luteum to continue secreting progesterone
Progesterone makes uterine glands wider, more tortuous & able to contain more secretions than during secretory stages.
Endometrium as whole becomes thicker duirng pregnancy.
Ectopic Pregnancy
Embryo implants in oviduct, whose lamina propria reacts like endometrium.
Oviduct later bursts due to growing embryo, causing extensive hemorrhage which can be fatal if not treated immediately
Placenta Previa
embryo implants close to internal os.
Placenta will be interposed b/t fetus & vagina.
If condition recognized fetus delived C-section
Zygote may enter abdominal cavity & implain in peritoneum
Cervix
lower 1/3 uterus
No spiral a. & epith not slughted off!
Endocervix= simple columnar, cervical glands
external os= squamous columnar junction
ectocervix= stratified sqamous non keratinized
Cervix
very watery secretion around ovulation to let sperm through. Stimulated by progesterone & estrogen.
Any other time its thick mucus
Cervical Ectropion
cervix protrudes into vagina where pH is low & cells change to sqamous epithelia.
Vagina
Fibrom. tubue, acts in transport of sperm to uterus & in expulsion of nebworn
mucosa: non keratinized stratified squamous epith, no glands, lamina propria
muscularis: inner circular & outer longitudinal
adventitia: dense CT, rich in elastic fibers
Vagina
Epith responds to hormonal changes
Glycogen stored in epith cells, reaches max levels @ ovulation after which time glycogen rich superficial layer of eptih is shed
Breakdown of glycogen by bac in vagina produces lactic acid, cause vaginal environment to have an acid pH of 3.
This low pH inhibits growth of other bac & fungus. Also limits sperm survival
Mammary Glands
ea gland has 15-25 lobes of compound tubuloalveolar type
Lobes separated by dense CT & adipose tissue. Ea lobe is really a gland in itself w/ its own excretory lactiferous duct
Breast enlargement during puberty is result of accumulation of adipose tissue & Ct w/ increased growth & branching of lacteiferous ducts due to increase in estrogen
True apocrine glands- sacrifice part of themselves!
Mammary Glands
stimulated by oxytocin when baby sucks on nipple
Milk ejection reflex
