unit 14 Flashcards
how are the cyclic changes that the female reproductive system undergoes controlled?
neurohumeral mechanisms
what is the function of the ovaries
produce sex steroids (estrogen and progesterone)
produce gametes
what is the composition of the ovaries from superficial to deep
germinal epithelium
tunica albuginea
cortex
medullary region
ovary germinal epithelium
covers surface of ovary
simple squamous, sometimes cuboidal
ovarian tunica albuginea
composed of dense CT, deep to germinal epithelium
white appearance
ovarian cortex
deep to tunica albuginea
contains follicles
ovarian medullary region
vascular bed, loose CT, lymphatics, and nerves
where are follicles found
embedded in the stroma of the cortex region
what does a follicle consist of
oocyte surrounded by layer(s) of follicular cells
what are the stages of follicular development
primordial
primary (preantral)
secondary (astral)
Graafian (mature)
primordial follicles consist of what
primary oocyte (large nucleolus & eccentric nucleus)
surrounded by single layer of squamous follicular cells (joined by desmosomes)
basal lamina surrounds that layer (boundary between follicle and stroma)
follicular cells in early primary follicle
proliferate to form a single layer of cuboidal cells
secrete steroid hormones & growth factors that promote oocyte development/maturation
what is the follicle called after the follicular cell form a single cuboidal layer?
unilaminar primary follicle
oocyte in early primary follicle
enlarges, secrete GAGs and glycoproteins that form zona pellucida
what is the zona pellucida
glycoprotein coat between the oocyte and follicular cells
what do follicular cells do in the late primary follicles
continue to proliferate, form a stratified epithelium called stratum granulosum
follicular cells are now called granulosa cells
other changes to late primary follicles
zona pellucida thickens and becomes visible
oocyte grows/matures, cortical granules form in cytoplasm and contain proteases
stromal cells differentiate and form a 2 layered CT sheath (theca folliculi)
layers of theca folliculi
theca interna - cuboidal, steroid producing secretory cells; fibroblasts and BV
theca externa - SM and collagen
secondary follicle
granulosa cells secrete fluid rich in hyaluronan, proteoglycans, and steroid binding proteins
stratum granulosum, 6-12 layers thick, fluid filled cavities form an antrum
oocyte reaches max size, positioned eccentrically in follicle
theca layers more distinct
mature follicle
mound of granulosa cells project into and line antrum, are called cumulus oophorus
oocyte suspended in antrum , surrounded by corona radiata, complete meiosis I, enters II
theca layers actively secrete hormones
where is a Graafian follicle located
just beneath the surface of the ovary, causes bulging
what causes expulsion of the secondary oocyte and corona radiata from the follicle
disruption of blood flow, creating avascular area that ruptures
protease-mediated weakening of the follicular wall
follicular fluid pressure
contraction of SM in theca externa
what happens if the oocyte is fertilized
completes meiosis II, becomes an ovum
what happens after the follicle remnant collapses
forms deeply folded structure around a cavity that fills with blood to become corpus hemorrhagicum
once this wound heals, structure remaining is called corpus luteum
corpus luteum
highly vascular and large
thick inner folds of granulosa lutein cells with cords of cells from outer layer theca lutein cells
what happens to the corpus luteum
if fertilization does not occur, degeneration and formation of corpus albicans
if fertilization occurs, maintained until parturition
what do lutein cells do
produce steroids (progesterone & some estrogens)
prepare the uterus for implantation
maintain early pregnancy
where do lutein cells come from
granulosa and theca interna cells increasing in size, filling with lipid droplets
what cells undergo atresia
primordial follicles that began the maturation phase but do not finish it
atresia in primordial and early primary follicles
oocyte and follicle shrink and degenerate at the same time
atresia in more mature follicles
death of granulosa cells, loss of oocyte
macrophages & neutrophils infiltrate granulosa layer
sloughing of granulosa cells into antrum
hypertrophy of theca interna
follicular collapse
what does FSH do during the cycle
stimulates follicular growth and secretion of estradiol
what happens to the dominant follicle?
becomes increasingly sensitive to FSH, LH, and estradiol
what does estradiol do
stimulates the hypothalamus to secrete gonadotropin-releasing hormone
stimulates anterior pituitary to secrete FSH
what does GnRH do
stimulates a surge of luteinizing hormone to be released from anterior pituitary
what does estradiol do
stimulates a lesser spike of FSH to be released
what does luteinizing hormone induce
primary oocyte completion of meiosis I
rapid build up of follicular fluid and swelling of follicle
secretion of enzymes that weaken follicular wall by macrophages and leukocytes
uterine tubes
narrow bilateral tubes that extend from uterus toward ovaries
infundibulum, ampulla*, isthmus, uterine
mucosa of uterine tubes
simple columnar epithelium containing ciliated (pale staining, motile!) and nonciliated (PEG cells, slender elongated nucleus) cells with underlying lamina propria
complex longitudinal folds, most complex in ampulla
muscularis of uterine tubes
thick, inner circular layer
thin, outer longitudinal layer
composed of visceral smooth muscle (peristalsis moves ovum into uterus)
thickness is greatest in isthmus
serosa of uterine tubes
outer serous membrane of mesothelium and thin CT
uterine tubes during menses
epithelial cells undergo cyclic hypertrophy during follicular phase, atrophy during luteal phase in response to hormonal changes
what affect does estrogen have on uterine tubes during menses
increases height of secretory cells, greatest around ovulation
stimulates cilia production, peak around ovulation
increases secretory activity
what affect does progesterone have on uterine tubes during menses
stimulates PEG cell proliferation
PEG cell number increases after ovulation
increases number of PEG cells
uterine blood supply
uterine artery branches > arcuate arteries (circle myometrium)
arcuate arteries divide > radial arteries (penetrate into myometrium)
endometrium - straight and spiral
stratum functionalis, capillary beds, lacunae - spiral
stratum basalis - straight
layers of the uterine wall, superficial to deep
perimetrium (outer serous layer, continuous with pelvic and abdominal peritoneum)
myometrium (thick, muscular, continuous with uterine tube and vaginal muscle)
endometrium (mucosa)
endometrium
simple columnar epithelium (ciliated and secretory cells) line lumen
endometrial glands penetrate down into underlying stroma
what are the layer of the endometrium
stratum functionalis
stratum basalis
stratum functionalis
thick, superficial endometrial layer
includes surface epithelium, upper part of glands, associated stroma
shed during menstration
stratum basalis
thin, deep endometrial layer
lower portion of glands, associated stroma
retained during menstruation, regenerates stratum functionalis
myometrium
composed of 3 indistinctly defined layers of SM
inner and outer are mostly longitudinal, middle is circular and spirally arranged
what are the 3 phases of the menstrual cycle
proliferative
secretory
menstrual
endometrium at the end of the menstrual phase consists of
thin band of Ct
basal portion of uterine glands and spiral arteries
straight arteries
what happens in response to estrogen in the proliferative phase
epithelial cells in glands proliferate, migrate to cover surface and elongate glands
stromal cells proliferate
spiral arteries lengthen
glands have narrom lumens and are mostly straight
stratum functionalis is regenerated
when does the proliferative phase end
one day after ovulation
what regulates the secretory phase
progesterone
what happens during secretory phase
stratum functionalis layer thickens, becomes edematous
cells hypertrophy
glands enlarge, become corkscrew shape, lumen has saw tooth appearance
spiral arteries lengthen and reach surface
what does the menstrual phase result from
decline in secretion of progesterone and estrogen
corpus luteum in menstrual phase
produces hormones for about 10 days if fertilization does not occur
hormone levels rapidly decline just prior to menstruation
corpus luteum changes cause what
periodic contractions of spiral arteries, this results in transient ischemia that leads to reduced glandular secretion, endometrial height shrinkage, leukocyte infiltration, RBC extravasation into stroma
extended contraction of spiral arteries causes
disruption of epithelium
sloughing of tissue and bleeding
this continues until only the stratum basalis remains
what is the chorionic plate
CT plate with vessels to/from the umbilical cord
stem villi > intermediate villi > free villi > anchoring villi
what is the decidual plate
composed of decidual cells (large, round, pale staining) covered by a layer of trophoblast cells
anchoring villi invade decidua
syncytiotrophoblast layer
epithelial-like outer layer that covers chorionic villi
early: nuclei evenly distributed, epithelium cuboidal
cytotrophoblast layer
proliferative middle layer
early: underlie syncytiotrophoblast
term: few cytotrophoblasts remain deep to syncytiotrophoblast
connective tissue stroma
found in the core of the villi
cellular stroma with mesenchymal cells, fibroblasts, SM cells, macrophage-like, antigen-presenting cells, fetal blood vessels whose lumens dilate over time
what is the placental barrier composed of
semi-permeable barrier between maternal and fetal circulation
syncytiotrophoblast layer
cytotrophoblast cells
trophoblast basal lamina
villous stroma/CT
endothelial basal lamina
endothelial cell
what can cross the placental barrier
gases, small molecules and drugs (low molecular weight, non polar, lipid soluble)
antigens and antibodies
some viruses
what is the cervical mucosa composed of
epithelial ranges from simple columnar epithelium with branched glands to stratified squamous epithelium
not sloughed during menstruation
mucus secretions impacted by cycle
cervix
robust CT stroma
modest muscularis
ectocervix
projects into vagina, comprised of stratified squamous epithelium
endocervix
lines cervical canal and is comprised of simple columnar epithelium with large, branched glands with mucus secreting cells
transformation zone
abrupt transition between ecto- and endo- cervix
most common site for cervical cancer
mucosa of vagina
numerous transverse folds
stratified, squamous, nonkeratinized epithelium
prominent lamina propria containing abundant elastic fibers
CT papillae from lamina propria project into overlying epithelium
muscularis layer of vagina
two intermingling SM layers, outer longitudinal and inner circular
the outer layer is continuous with the corresponding layer of the uterus and much thicker
adventitia of vagina
inner layer of dense CT with numerous elastic fibers
outer loose CT layer, numerous blood and lymphatic vessels, nerves
histology of vaginal mucosa
stratified squamous, non-keratinized epithelium, some thickening during luteal phase, NO glands, produces glycogen
cellular, loose CT lamina propria with many WBCs, elastic fibers, and rich vascularization
what is the breast composed of
glandular tissue embedded in subcutaneous adipose and CT
suspensory ligaments suspend breast from deep fascia
breast glandular tissue
branched modified sweat glands that produce milk
organized as 15-20 lobes per breast, radiate out from nipple
breast glandular lobes
branched ductal system with branches ending in many lobules
breast glandular lobules
functional unit of mammary glands
composed of central interlobular duct with branches ending at terminal ductules surrounded by loose interlobular CT
when do true alveoli form
during pregnancy
intralobular duct epithelium
simple columnar/cuboidal secretory
terminal ductal lobular unit
lobule + associated extra lobular terminal duct (connects intra to inter duct)
most breast cancers arise in TDLU
what is the glandular tissue of the lobule surrounded by
loose intralobular CT
duct order
intra > extra > inter > main
breast interlobular stroma
dense irreglar CT and adipose
surrounds lobules and interlobular ducts
luminal epithelial cells
near nipple - stratified squamous
lactiferous sinus - transitions to simple cuboidal
what happens beginning at the sinus
myoepithelial cells surround the epithelium
where are luminal and myoepithelial cells derived from
basally positioned stem/progenitor cells
histology of inactive mammary gland
abundant interlobular stroma (DCT)
sparse glandular tissue
small ductal lumens
consists of sparse ductal structures surrounded by abundant loose CT
slight changes during menstrual cycle
pregnancy induced changes in mammary glands
glandular epithelium and myoepithelial cells proliferate, increase ductal branching, alveoli develop
luminal cells begin to differentiate and produce milk
decrease in intralobular and interlobular stromal CT, adipose tissue
lactating mammary glands
alveoli more uniform in size
abundant lipid secretions in lumens
tight junctions between secretory cells ensure luminal storage of secretions
ultrastructural changes to lactation mammary gland
spherical nucleus more basally positioned
increase in apical secretory vesicles and lipid droplets
hypertrophy of ERs, Golgi
numerous apical microvilli
mammary secretions
milk proteins (exocytosis)
lipids (apocrine secretion)
IgA from plasma cells transcytosed
