Histology

puberty is initiated by the secretion of

gonadotropic hormones

menarche

first menstrual flow, end of puberty

female genital system

internal reproductive organs (ovaries, oviducts, uterus, vagina) external reproductive organs (clit, labia), mammary glands

ovary epithelium

simple cuboidal epithelium

tunica albuginea

poorly vascularized dense irregular CT in ovary + testis

ovary is divided into

hilus, cortex, medulla

role of ovary

gametogenesis + steroidogenesis (estrogen + progesterone)

estrogens role

promote growth + maturation of sex organs, responsible for female sex characteristics, breast dev

progesterens role

prepare internal sexorgans (uterus) for pregnancy, mammary gland for lactation

ovarian hilus

place where blood, lymph and nerves enter and exit ovary, w/ ovarian hilar cells

where are vestigial remnants of wolff channels found

ovarian hilus

characteristics of ovarian hilar cells

large, round w/ granular or vacuolar eos cytoplasm, sometimes w/ lipofuscin pigment or Reinke crystalloids

__________ respond to hormonal changes during pregnancy and at menopause onset

ovarian hilar cells

cortex of ovary is composed of

stroma (CT), ovarian follicles, corpus luteum, corpus albicans, atretic follicles

stroma of ovary

fibroblast-like stromal cells, reticular + collagen fibers, smooth m cells

stroma is a ___________-dependent structure

hormonal

before the onset of puberty all follicles of ovarian cortex are in which stage?

primordial follicle stage

at puberty, what hormones are secreted

GnRH (by hypothalamus), FSH + LH (from pituitary)

four dev stages of ovarian follicles

primordial, growing (primary + secondary), mature (graafian)

ovarian development is dependent on which hormone

FSH secretion

primordial follicles first appear when

third month of fetal development

where are primordial follicles located

under tunica albuginea, in groups

composition of ovarian follicles

squamous follicular cells, primary oocyte, BM (→ then stroma)

2 types of primary follicles

* unilaminar/layered


* multilaminar/layered - late primary

unilaminar/unilayered primary follicle

follicular cells become cuboidal, primary oocyte secretes specific proteins → zona pellucida (bw oocyte + adjacent follicle cell), formed of glycoproteins,

multilaminar/multilayered - late primary follicle is made of?

follicular cells undergo rapid mitotic proliferation and stratify → cell layers around primary oocyte → membrana granulosa

theca folliculi

stromal cells surrounding follicles forming CT sheath, of primary follicles

__________ have receptors for FSH

follicular/granulosa cells

what is required for a developing follicle

FSH, GFM, Ca+2 ions

secondary (antral) follicles are similar to primary follicles except for

presence of accumulation of fluid among granulosa cells

what is inside secondary (antral) follicle’s cavity

fluid-filled cavities (liquor folliculi) among granulosa cells, w/ glycosaminoglycans, proteoglycans, hormones → antral follicle

components of secondary (antral) follicles

* oocyte - eccentric, lipid deposits
* zona pellucida
* membrana granulosa → antrum, w/ FSH receptors
* BM
* stromal cells - around follicle
* theca interna - highly vascularized, LH receptors, fibroblasts
* theca externa - CT, collagen + SM fibers

secondary antral follicle contains ________ which is secreted by granulosa cells

oocyte maturation inhibitor

graafian (mature) follicle

the follicle that undergoes ovulation

components of graafian (mature) follicle

* antrum (w/ liqour folliculi)
* cumulus oophorus - primary oocyte
* corona radiata - layer granulosa cells
* membrana granulosa - FSH + LH r (downregulated)
* BM
* theca interna - well dev, secretes androgens, endocrine appearance
* theca externa - fibrous CT

follicular stigma

at ovulation, graafian follicle extends through whole ovarian cortex and causes a bulge on the surface → blood flow stops and ovary surface ruptures

what happens in ovulation after follicular stigma occurs

release of secondary oocyte from ruptured follicle (oocyte traverses follicular wall, secondary oocyte is arrested in metaphase), estrogen and progesterone secreted by corpus luteum

how do the hormones and enzymes cause ovulation

* increase v + p of follicular fluid
* enzymatic proteolysis of follicular wall by plasminogen
* glycosaminoglycans bw oocyte-cumulus complex + stratum granulosum → loosened
* contraction smooth m fibers in theca ext, by PGs

what happens at ovulation in uterine tube

fimbriae of uterine tube become more superficial, cumulus mass w/ oocyte is swept by fimbriae into uterine tube → ciliated cells of uterine tube

what happens if fertilization doesn’t occur after ovulation

secondary oocyte degenerates as it passes through uterine tube

what happens to oocyte that fails to enter uterine tube

degenerates into peritoneal cavity, rarely ectopic implantation (Douglas or in oviduct)

corpus luteum is formed from

remnants of graafian follicle (granulosa + thecal cells)

_________ is a temporary endocrine gland that releases hormones that support endometrium (estrogen + progesterones)

corpus luteum

after ovulation, what happens to corpus luteum

follicle wall (granulosa + thecal cells) collapse, bleeding from caps → theca int into follicular lumen forming corpus hemorrhagicum, CT invades former follicular cavity, luteinization (granulosa + theca interna cells → luteal cells)

corpus luteum is composed of

granulosa-lutein cells (modified granulosa cells) and theca-lutein cells (modified theca interna cells)

granulosa-lutein cells

centrally located, large, of corpus luteum, secretes progesterone

theca-lutein cells

smaller, peripherally located, secretes progesterone and estrogens, of corpus luteum

in absence of fertilization the corpus luteum

degenerates 10-12 days after ovulation from absence of hCG and luteotropins

when does corpus luteum begin to decline in pregnancy

after 6w of pregnancy (taken over by placenta), declines after 8w

corpus luteum after pregnancy

degenerates (involution), cells loaded with lipid, white scar forms → corpus albicans

corpus albicans

formed as intercell hyaline material, after corpus luteum degeneration, persists as scar

atretic follicles

follicles that undergo degeneration

ovarian medulla

richly vascularized fibroelastic CT made of CT cells, interstitial cells (secrete estrogens), hilar cells (secrete androgens)

4 anatomical regions fallopian tubes

intramural region, isthmus, ampulla (fertilization), infundibulum (

uterine tubes walls are composed of 3 layers:

mucosa (simple columnar epithelium w/ ciliated and nonciliated peg cells), musculris

what changes do epithelial cells of uterine tubes

hypertrophy during follicular phase, atrophy during luteal phase in response to changes in hormonal levels

uterus receives the rapidly developing _________ from the uterine tube

morula

uterus is divided into 3 regions

fundus, body, cervix

uterine wall of body and fundus is composed of what layers

endometrium, myometrium, perimetrium

perimetrium layers

outer serous layer (all of post layer and some of ant layer), adventitia (ant layer)

myometrium layers

thick smooth muscle layer - inner and outer layers, middle circ (stratum vasculare)

all 3 layers of ______ work together as a fxnal syncytium

myometrium

\# of myometrial m cells are related to

estrogen levels

increase in uterine size in pregnancy is due to

hypertrophy of smooth m cells and hyperplasia

endometrium

mucosal lining of uterus, consisting of 2 layers (stratum functionalis, basalis)

stratum functionalis and basalis differences

functionalis - hormone sensitive, w/ coiled arteries

basalis - retained during menstruation, non-hormone sensitive

endometrium layers

simple columnar epithelium (secretory columnar cells, ciliated cells), lamina propria (endometrial stroma)

before puberty the endometrium is what epithelium

simple cuboidal epithelium

endometrial stroma

collagenous CT (star shaped, macrophages, leukocytes, reticular fibers)

how are uterine glands formed

invaginates into underlying lamina propria (simple branched tubular glands made of nonciliated secretory columnar cells), vessels

where do vessels proliferate and degenerate during each menstrual cycle

endometrium

uterine artery gives off what

6-10 arcuate arteries that anastomose in myometrium → radial a → endometrium → small straight arteries → spiral a

main branch of radial a continues and coils, called ________ __→ arterioles →__ _________

spiral artery

lacunae

which vessels in endometrium are under influence of estrogens and progesterones

distal spiral arteries

what happens during menstrual phase

hormones in ovary declines (periodic contractions of spiral arteries, stratum functionale necrosis), degeneration of corpus luteum, desquamation of functionalis layer of endometrium

proliferative phase is influenced by

ovarian estrogen secretion

secretory/luteal phase effect on endometrium

fxnal activity of corpus luteum, influenced by progesterone secretion, thickening of endometrium (edematous, glands hypertrophy + coiled, spiral arteries go to surface), secretory products accumulate in basal region (subnuclear vacuoles) → supranuclear vacuoles (towards basal cell) → glands, stromal cells become decidual cells

endometrium is controlled by

gonadotropins secreted by pars distalis of pituitary that regulate steroid secretions of ovary

follicular phase begins with dev of what under the influence of what

primary ovarian follicles, FSH + LH

FSH influences what

growth of follicles, stimulates granulosa + thecal cells → secretion steroid hormones

ovulation is induced by a surge in

LH level

what happens during luteal phase

granulosa + thecal cells of ruptured follicle undergo rapid transformation to form corpus luteum, estrogen + progesterone secreted by corpus luteum

what happens to endometrium during proliferative phase

reepithelization of endometrium lining and renewal of functionalis (reconstruction of glands, CT, slightly coiled a from residual basalis), accumulation glycogen in epithelial cells, stromal cells secrete collagen and ground substance, glands have narrow lumen and wavy

in what phase is the implantation of blasocyst which enables transformation of stromal cells into decidual cells

secretory (luteal) phase

cervix

terminal end of uterus that protrudes into vagina, terminal part called portio vaginalis/ectocervix

endocervix

runs along its entire length, connects uterine cavity and vaginal lumen

internal vs external os

opening into uterus vs opening into vagina

cervix is nulliparous vs multiparous women

nulliparous circular, multiparous transversal slit

ectocervix

lower part of cervix that projects into top of vagina

lamina propria of endocervix contains

cervical glands (large, branched, mucous-secreting)

lumen of cervix is lined by

mucus-secreting simple columnar epithelium, extending to branched cervical glands

functions of cervical glands

transport spermatozoa

cervical mucus in proliferative phase

amount increases, less viscous, aqueous, alkaline ph (favourable for sperm migration)

changes to cervical mucous after ovulation

viscous, reduced, acidic ph

exocervix is covered by

stratified squamous nonkeratinized epithelium

transition zone of external os

SSE covering ectocervix and mucus-secreting columnar epithelium of cervical canal (endocervix)

ectropion

under influence of hormones secreted at puberty, cylindrical epithelium area descends towards ectocervix

why does vaginal ph become acidic after puberty

bacterial degradation of glycogen from squamous epithelial cells

what occurs during “transformation area” of endocervix epithelium and exocervix epithelium

columnar → squamous epithelium (exposure to acidic enviro)

uterus changes during pregnancy

myometrium increases (hypertrophy + hyperplasia), endometrium suffers decidual changes (progesterone), placenta forms