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