female reproductive - histology Flashcards
ovary- repairs itself each month via?
Lgr5+ stem cells
ovarian surface epith OSE -
ovary has outer cortex and central medulla -
cortex of ovary?
SWIRLY stroma - numerous spindle shaped fibroblasts - that specialize in responding to hormones
primordial follicles - at periphery of cortex is tunica albuginea
medulla of ovary?
loose fibroelastic CT, blood vessels, lymph, nerves - with smooth muscle fibers
Pre puberty in swirly stroma?
primordial follicles -
sex maturity defined by GROWING Follicles
after menopause - follicles disappear - cortex becomes fibrous
follicular phase - 5
primary (unilarered)
Secondary (multilayered)
Pre antral
Antral
Graffian - (preovulation)
ovarian cycle - 3?
follicular
ovulatory
luteal
primordial?
squamous (granulosa single layer) surrounde cell
primary follicle 3 things
- zona pellucida begins -
- granulosa cells becomes cuboidal
- theca cells from on outside of basal lamina
secondary - multilayered 3
- zona pellucida finished
- stratified multilayered granulosa
- theca interna layered also - 2 layers or so
preantral -
lakes starts to form inside
blood vessels form in area of
theca externa forms
fetal development - where do primordial germ cells OOGONIA migrate from?
Yolk sac to ovarian cortex -
and MULTIPLY by mitosis
by 4-5 month - some enlarge - and assume potential becoming PRIMARY OOCYTES - and commense first stage of meiotic division
by 7th month - what happens to primary oocyte?
becomes encapsulated by single later of flattened follicular cells - to form PRIMORDIAL FOLLICLES
what do follicular cells produce? pre-pubery?
INHIBITs
oocyte maturation inhibitor - to prevent earlier completion of meiotic prophase
primary oocytes are arrested in what state?
Prophase 1 - 46 n - arrested in Meiosis 1
Prophase 1 is essentially the crossing over and recombination of genetic material between non sister chromatids - this results in the genetically unidentical, haploid daughter chromatid cells
after puberty - what happens to follicular cells each month?
~~ 20 primodial follicles mature into primary follicles - some into secondary -
primary that do not mature?
atresia
What stage of development is ovulated egg?
Secondary OOCYTE - arrested in metaphase II
it has now genreated 1 polar body that degenerates - hhas 23
if fertilized what happens
meiosis II completed - second polar body degenerates - beomces and OVUM
ovum?
after fertiliation - this is what they call it
What is a vesicular follicle? typically only one secondary follicle becomes a vesicular follicle
a secondary follicle ready to ovulate - with 23 haploid - arrested in Meiosis II - has generated first polar body
if secondary oocyte doesn’t become fertilized?
degenerates
what happens to shell of follicular body - after the follicle has been released?
corpus luteum - secretes Progesterone (and inhibin and estrogen)
preparing uterus for implantation
dictyotene?
resting phase of primodial follicle - arrested at prophase I - at the DIPLOTENE state
are all female germ cells present at birth?
Yes, and meiotic division is completed between aged 15 - 50
total number of follicles at birth?
400,000 - most will disppear by ATREsia - begins prior to birth and spans entired life
atresia? which cells?
can affect any - even ones that are nearly mature
total number of ovum liberated during a woman’s life?
450 -
atresia is increased when? 3 xs
just after birth when effects of maternal hormones cease and also during puberty and pregnany?
how does atresia occur?
apoptosis - macrophages invade and degenerate and clean up debris - avoiding an inflammatory response
glassy membrane?
see them as folded perhaps
The basement membrane that separates the granulosa cells from the vascularized theca interna persists in these atretic follicles and appears as a collapsed structure the “glassy membrane”.
What replaces the degnerated follicles via atresia?
scar - called CORPUS ALBICANS
When are primoridal follicles most numerous?
before birth - large nucleus, numerous mitochondria, sevearl Golgi
Squamous follicular cells contain ER, mitochondria and lipid droplets - marks boundary between avascular follicle and surrounding stroma
is primordial follicle avascular?
yes
primary function of follicles NOT becoming the ONE to be released - the vesicular?
MAY BE … to act as Endocrine gland - because releasing Estrogen - signaling hypothamus to keep the FAH and LH lower - by the negative feedback llop…
What stimulates follicular maturation?
FSH - fastest growth early - folliicular cells form a signel layer of cuboidal cells and in now a UNILARMINAR primary follicle
follicular cells proliferate via mitosis and form a stratified layer (granulosa layer) - now a MUTILAMINAR primary follikcle
What’s in the zona pellucida coat?
ZP 1, 2, 3 - glycoproteins secrete by oocyte -
Fillipodia of follcicular cells and microvilli of oocyte make contact with one another via GAP Junctions
is the granulosa layer at this point with blood vessels?
NO
Theca cells form around follicle -
two layers
theca interna - cuboidal - PRODUCE Steroids when completely differentiated - they have LH receptors - rich vascularization - fibroblast, collagen
theca externa - collagen bundles and smooth muscle
basal lamina THICK between granulosa and theca
follicular cells produce what hormone?
No other ovarian cells are known to have FSH receptors. Granulosa cells of the ovulatory follicle are the major and virtually only source of estradiol in the follicular phase of the ovarian cycle and secrete estrogens in response to FSH. … LH stimulates thecal cells to produce androstenedione.
Estadiol - when stim by FSH - BUT depend on theca interna cells - regulated by LH
Theca cells produce? stinulated by LH
androstenedione - which is needed by follicular to produce estradiol
FSH receptors?
in primary and secondary follicle - they have FSH receptors - in Graafian follicle - LH receptors appear and coexist with FSH receptors -
acquisition of LH receptors is essential for luteinization 0f ruptured follicle following ovulation
secondary follicles - where does clear fluid come from?
plasma in capillaries adjacent to follicle - and modified by granulosa cells -
liquor folliculi -
from ANTRUM
these follicles are called secondary “vesicular “ or antral follicles
increases in amount as follicle enlarges - caviites eventually fuse and form one cavity ANTRUM
cumulus oophorus?
almost like a stalk that the oocyte is seated upon
hillock of granulosa cells - which contain oocyte - doesn’t grow anymore - surrounded by single layer of cuboidal follicular cells - where apical processea are firmly anchored in zoma pellucida -
CORONA RADIATA - nourishes oocyte - gap junctions - share resources -
in growing follicles - PAS+ve?
Call-Exner bodies may appear ??
how many days do follicles take to reach maturity
10 - 14 - can be seen bulging from surface of ovary -
anovulatory cycles?
absence of ovulation and a luteal phase. In the absence of ovulation, there will be infertility.
upon rupture?
ovum and granulosa cells immediately surrounding it are loosened from cumulus oophorus and floast freee in liquor folliculi
The cumulus oophorus,
also called discus proligerus, is a cluster of cell (called cumulus cells) that surround the oocyte both in the ovarian follicle and after ovulation. In the antral follicle, it may be regarded as an extension of the membrana granulosa. The innermost layer of these cells is the corona radiata.
how do growing oocytes receive nutrition?
gap junctions enable metabolic cooperation betw oocyte and granulosa cells - trasnfering nutrients
Connexi 37 and 43
37 present in gap junctions bewteen granulosa to oocyte
43 between granulosa cells
Transforming Growth Factor
GDF9 and BMP15 function in cooperative manner to regulated energy and cholesterol biosynthesis of granulosa cells - enhancing female fertility
GDF 9
also required for formation by granulosa cells of cell processes that penetrate and cross the zona pellucida
ovulation?
note LH surge helps in rupture of ovary cortex
Edema and collagenases weaken wall
at ovulation - oocyte and corona radiata are expelled
appearance of stigma (macula pellucida) - where BURSTING occurs
proteases from LH surge degrade collagen fibers of tunica albuginea and theca externa
germinal epith becomes discontinuous - stroma thins
flow of blood on outer surface of ovary thins and stops - local changed in color
stigma buldges oustward as a clear vesicle rputures -
fibriae of oviduct are close at this time - drawing ovum in
difference between corona radiata and zona pellucida?
The key difference between zona pellucida and corona radiata is that zona pellucida is a non-cellular secretory glycoprotein layer that surrounds the plasma membrane of mammalian ovum while corona radiata is a follicle cell layer that surrounds zona pellucida for nourishment -
upon rupture - corpus luteum
granulosa cells (mural now called?) left behind fold and become lutein granulosa cells - basal lamina breaks down = folding, antral cavity is filled with blood - corpus hemorraghicum
during ovulation?
The cell is in metaphase II when the chromosomes align themselves along the metaphase plate through the facilitation of the spindle fibers. The spindle fibers are now attached to the two kinetochores contained in the centromere of each chromosome.
cell viable for 24 hours - begins second meiotic division - stopping at metaphase II stage - which will only be completed if fertilized
When is first polar body expelled?
while still in ovary -
when is second polar body cast off?
if fertilized
2 polar bodies are formed during the complete process of oogenesis in human females.
function of polar bodies?
Polar bodies serve to eliminate one half of the diploid chromosome set produced by meiotic division in the egg, leaving behind a haploid cell. To produce the polar bodies, the cell must divide asymmetrically, which is fueled by furrowing (formation of a trench) near a particular point on the cell membrane.
theca internal follicular cell synergism?
FSH stimulates follicular growth which. LH stimulates theca cells to produce androstenedione - which is transferred to granulosa cells for its aromatization into estrogen
what stimulates the LH surge?
vesicular follicle produces threshold amount of estrogen which triggers surge
estrogen and FSH late in follicular phase - no negative feedback loop now working
if pregnancy not occur - when does luteinlysis begin?
7 days- and then progesterone drops, inhibin and estogen drop - FSH begins - leading to menstruation
during early follicular stage - how is FSH and low levels of estrogen created?
secretion of inhibin keep estrogen levels low and FSH levels low despite GnRH growing
after ovulation - what kind of organ does corpus luteum becomes?
an endocrine organ -
LH causes granulosa cells to differentiate into granulosa lutein cells -
theca interna differentiate into theca lutein cells
both new cells produce PROGESTERONE and Estrogen
what color is corpus luteum?
yellow - due to yellow lutein pigment
stays within ovary - generating progesterone and estrogen -
progesterone prevents?
development of new ovarian follicles and further ovulation
becomes folded when follicular fluis is released
corpus lutein - granulosa cells change character
into steroid secreting cell with lipid droplets = grow greatly in size - there were protein secreting cells!
theca lutine cells?
Theca lutein cells secrete androgens and progesterone. Theca lutein cells are also known as small luteal cells.
stain darkly, smaller, in folds of CLuteum -
Corp luteum if no pregnancy becomes?
white scar - cropus albicans
Theca lutein cells?
store lipids - become larger
what hormones regulate corpus luteum?
FSH and LH -
FSH stim production of progesterone and estadiol by granulosa lutein cells and theca cells - androstenedione - for aromatization into estradiol
during pregnancy?
prolactin and placental lactogens up regulate effects of estradiol produced by granulosa lutein cells by enhacing the prodcution of estrogen receptors
estradiola stim granulosa lutein cells?
to take up cholesterol from blood - which is then stored in lipid droplets and transported to mitochondria fro progesterone synthesis
endometrial prostaglandin F2a trigger apoptosis
and luteolysis
if pregnancy not occur -
luteoloysi involves programmed death - this triggers is -
followed by reduction in blood flow causing a decline in oxygen
T cells reach corpus luteum and produce interferon Y - which brings out macrophages -
macrophages produce tumor necrosis factor igand and apopptiotic cascade starts
how do theca lutein cells create steroids?
granulosa lutein cells make up 80% and are in the center area - theca are on the edges - secreting androgens and progesterone
theca cells stimulated by LH take up cholesterol of LDL or both from blood - steroid production begins - androstenedione - is transported to follicular lutein cells
can store and use for synthesis of progesterone
follicular lutein cells utilize androstenedione - delivered by theca lutine cells to produce estradiol
When pregnancy occurs?
RELAXIN
chorionic gonadotrophin produced by placenta will stimulate corpus luteum (which is maintained for about 6 months) and then declines - conintuing to secrete progesterone until end of pregnancy
also secres RELAXIN - softens symphysis pubica
Theca cells - also can become INTERSTIIAL cells
surviving apoptosis during atresia - and secrete steroids- - called interstitial glands - sources of ovarian androgens
polycystic ovarian disease? excessive amounts of male hormone
cysts form - ovaries enlarge - excessive amounts of male hormone - unusually thick tunica albugenia - egg follicales mature but not released from ovary
uterine tubes?
four parts
infundibulum
ampulla
isthmus
interstitial part
3 layers of wall of uterine tube - mucous, muscular, external serous
fallopian tubes - two types of cells
secretory PEG cells
cilia - and non-ciliated (PEG cells)
cilia beat upward toward uterus - causing movement of viscous liquid covering its surface
liquids- nourishment- for sperm and egg produced by PEG cells
cilia changes during ?
the monthly cycle - taller, more during follicular phase -
fertilization occurs mostly?
at Ampular- isthmic junction
ectopic pregnancy? decidual cells
lamina propria reacts as does the endometrium - forming numerous decidual cells
The interglandular tissue is also increased in quantity, and is crowded with large round, oval, or polygonal cells, termed decidual cells. Their enlargement is due to glycogen and lipid accumulation in the cytoplasm allowing these cells to provide a rich source of nutrition for the developing embryo.
ciliogenesis?
is estrogen dependent - reach a max height during ovulation
non ciliated cells PEG cells?
provide nutrients to egg / sperm
muscular layer in fallopian tubes?
peristaltic waves help move ovum down tube -
serosa - loose CT surfaced with mesothelium
Syncytiotrophoblast
is the epithelial covering of the highly vascular embryonic placental villi, which invades the wall of the uterus to establish nutrient circulation between the embryo and the mother.
What is the role of syncytiotrophoblast during implantation?
W
Secretion of proteolytic enzymes which erode the endometrial epithelium and the stroma of the endometrium, so that the blastula can penetrate, and get implanted in the endometrium.
Window of uterine receptivity?
Endometrial receptivity is defined as a temporary unique sequence of factors that make the endometrium receptive to the embryonic implantation (2). It is the window of time when the uterine environment is conductive to blastocyst acceptance and subsequent implantation
corpus luteum makes possible by secreting estrogen and progesterone
at puberty, what stimulates primordeal oocytes to develop?
FSH
What nourishes follicular cells?
simple squamous follicular cells - they have FSH receptors - and are the primary regulators of follicle development
how do granulosa cells develop?
once folicle cells are stiumulated by FSH - they become granulosa cells - become cuboidal
What main difference is there between primary and secondary follicular cells?
extracellular fluid accumulation
when do primary oocytes complete 1st meiotic division?
a few hours before ovulation - in response to LH surge and FSH - paired chromosomes separate - the first polar body - this occurs between germ cell plasma membrane and zona pellucida - -
When ovulated - what is the status of the oocyte?
Secondary oocyte - has completed Meisosi I a few hours ago - along with the first polar body -
how to avoid multiple sperm fertiziling egg?
exocytosis of cortical granules, membrane depolatization, and enzyme mediated modificaiton of zona pellucida
what cells trigger atresia and apoptosis?
granular cells
all women’s ovaries will show?
collagen scar tissue from corpus luteus dying and leaving scar tissue
theca leutin cells secrete?
progesterone - and gather in groups in folds - are little and dark
What secretes a hormone that maintains endocrine function of corpus luteum during first 5 months of pregnancy?
syncytiotrophoblast they secrete hCG -
PEG cells in uterine tube ?
nourish egg, sperm, and promote sperm capacitation
most ectopic pregnancies occur
in ampulla or uterine tubes
double bicornate uterus caused by?
fusion of paramesonephric ducts -
proliferative vs secretory phase
What does secretory phase endometrium mean?
After ovulation occurs, the endometrium enters the luteal or secretory phase, which means that the lining has undergone a series of changes which will prepare it for a possible pregnancy. If pregnancy does not occur, the thickened endometrium will be shed during menstruation.
The progesterone surge of ovulation ends the proliferative phase, and the endometrium moves into the secretory (or luteal phase) of development. Under normal conditions the secretory phase is 14 days
secretory phase looks like
uterine glands become enlarged and coiled and tortuous - zig zag appearnce on slides - they secrete a glycogen fluid and provides a great growth medium for early embryo
uterine gland becomes juicy - with extravascular fluid plumping it up - also plumped because of growth of uterine glands
within two weeks of conception - what hormone can you find and where does it come from verifying pregnancy?
trophoblast - Human chorionic gonadotropin keeping corpus luteum functioning for 4 -5 months
are cells that form the outer layer of a blastocyst and are present four days post fertilization in humans. They provide nutrients to the embryo and develop into a large part of the placenta.
The syncytiotrophoblast is composed of fused cytotrophoblasts which forms a layer that covers the placental surface. ighly vascular embryonic placental villi, which invades the wall of the uterus to establish nutrient circulation between the embryo and the mother.
decidual cells?
ectopic pregnancy. Decidual cells found outside inner lining of the uterus are called ectopic decidual cells or ectopic decidua.
false pregnancy associated with abnormal growth of?
trophoblast
