Sept4 M1-Histology_Female_RS Flashcards
menarche def
- first menstrual flow at 13 years approx
- cyclicity of 28 days starts
- stops at menopause at 51
parts of the ovary (histo)
- germinal epith (surrounding ovary) (cuboidal simple epith)
- tunica albuginia under the germinal epith (thick layer of CT)
- cortex (follicles. lot of small ones on periphery, granular appearace)
- medulla (part close to hilus) (rich in loose CT, large pop of vessels)
- corpora atretica (scars from follicles replaced by CT)
- developing follicle(s)
- corpus luteum
- hilus (like a hilum)
- blood vessels (near hilus)
follicles develop where in the ovary
cortex
steps of primordial follicles formation
- primordial germ cells (derived from yolk sac which is separated from the fetus) travel and wander until reach the UG ridge. There, transform into oogonias (divide a lot.) 600 000 at 2 months, 700 000 at 5 months). eventually reach ovary when done travelling
- between month 3 and 7 of embryo, most oogonia begin to enter prophase 1 (occytes) but stop at the diplotene stage (step 4 of prophase 1) (sister chromatids together, homologs separated, actively transcribing)
- birth = 150000-400000 oocytes total (both ovaries). only 500 will mature
when is the first meiotic division of a primordial follicle COMPLETED
when it completes all steps for ovulation and is ovulated**
what is found under the tunica albuginia in the cortex
large pop of follicles including primordial follicles
primordial follicles charact
- smallest ones
- surround by flat follicular cells
- contain an oogonia
step after primordial follicles
primary follicles (unilaminar) (transformation from primordial to primary only starts at puberty**)
- contain a primary oocyte
- surrounded by ONE layer of cuboidal epith of follicular cells called granulosa cells
- GCs rest on BM outside of the cuboidal epith
ovulation def in terms of meiosis
completion of first meiotic division
when primordial to primary unilaminar transformation occurs and why
- at puberty (age 13 approx)
- is dependent on FSH
step after primary follicle unilaminar
primary follicle multilaminar regulated by FSH
- GCs divide forming many layers
- last layer resting on BM (so epith cells)
what happens in primary follicle multilaminar regulated by FSH after the many layers of GCs formed
- GCs close to oocyte start to make an EC material called zona pellucida (with small contribution from oocyte)
- around the follicle (out of BM), stromal fibroblast-like cells differentiate into a theca
step after the developed primary multilaminar follicle
secondary (antral follicle)
- GCs make a liquor folliculi, forming cavity called antrum
- antrum enlarges with time
stage of meiotic div of oocyte in secondary antral follicle
prophase 1 diplotene
what happens in secondary antral follicle after antrum formed
theca cells diff into theca interna and externa that is vascularized and very rich in capillaries
what does theca interna of secondary antral follicle do
theca interna cells have a big SER and make androstenedione
what does the theca externa of secondary antral follicle do
is just a layer of fibrocytes appearing darker than the interna
appearance of theca interna of secondary antral follicle on histo
H and E on LM = spaces in theca bc. The lipids (steroids) of the SER are not staining well, typical of steroid producing
what happens to androstenedione produced by theca interna cells in the secondary antral follicle
GCs use aromatase enzyme to transform androstenedione into estradiol
what happens in the developing secondary antral follicle
- antrum becomes larger (more follicular fluid made)
- fluid invades GCs
- GCs divide into group close to oocyte (cumulus oophorus)
name of layer of GCs of the cumulus oophorus that is closest to the oocyte and its function
corona radiata. is the GCs that where making the ZP. now being called the corona radiata
what happens to the oocyte through the diff steps: primordial, primary uni and multilaminar and secondary (antral) follicles
gets bigger because it accumulates cytoplasmic components
step after secondary (antral) follicles
of all the secondary antral follicles, one will develop into a mature, Graafian follicle
-the antral fluid goes in the back of the oocyte (still stuck to GCs) and the corona radiata (with the oocyte in its middle) will be released in the lumen of the antrum and float there.
steps of ovulation
- LH surge causes release of PGs + histamine + powerful enzyme collagenase
- collagenase dissolves stuff where Graafian follicle is (dissolves the tunica albugenia at the level of the stigma. stigma = where Graafian follicle bursts out)
- the germinal epith underneath the Graafian follicle separates
- oocyte + corona radiata floating in antrum are released and captured by the fimbriae
- local edema
- released oocyte completes 1st meiotic division
fimbriae histo
fingers projecting to ovaries. mucosa associated SM cells
FSH function in menstrual stage (as increases)
recruits a number of multilaminar primary follicles
- get bigger
- reach antral secondary stage
- one becomes dominant
- the rest can stay for next menstrual cycle or become atretic
signs of follicle degeneration on histo
- GCs dying
- ZP disappearing
- no nucleus in oocyte
- when die, all replaced by CT
follicular atresia (corpus lutea atretica) early stage
- see antrum + ZP
- most GCs dying
- CT invades
- capillaries and the scar form
follicular atresia (corpus lutea atretica) advanced stage
- oocyte gone
- ZP gone
what happens to the Graafian follicle when the oocyte + coronata radiata leave it (ovulation)
- collapses into a corrivated structure (corpus luteum)
- small theca cells are drawn in ridges of the big GCs, forming folds.
- blood vessels from the periphery (from the highly vascularized theca interna) enter the folds, ridges with the theca cells
- GCs become granulosa lutein cells making E and P
- theca interna cells form theca lutein cells also making E and P
- a blood clot forms during bleeding
GLCs vs TLCs (corpus luteum)
GLCs = large, less acidophilic, paler TLCs = small, more acidophilic, lot of blood vessels with them (caps)
corpus luteum life steps
- persists for 14 days
- after that, becomes the big corpus albicans (white keloid tissue)
- corpus albicans = scar lasting months to years in ovary
when the first meiotic division of the oocyte is completed ? dependent on what
after ovulation. is LH dependent (part of the LH surge)
what is the result of the first meiotic division of oocyte
- one secondary oocyte forms and keeps all the cytoplasm
- the other daughter cell is the polar body
what does the secondary oocyte from 1st meiotic div do
engages in 2nd meiotic division steps* (not dividing) until metaphase 2
when does the secondary oocyte complete its 2nd meiotic div
- if fertilization occurs (sees male spermatozoa)
- a second polar body forms
steps of fertilization
- binding of sperm to ZP
- acrosomal reaction
- penetration through ZP
- fusion of plasma membranes
- sperm nucleus enters egg cytoplasm
acrosome system, reaction def
- process by which enzymes are released (of the acrosome of the sperm (tip of the sperm))
- they dissolve the corona radiata so that the sperm can penetrate the ZP
how many sperms interact with the oocyte + consequence
- many sperms
- no consequence, no other sperm can enter after first one
ovarian cancer develops from what cells usually
germinal epithelium. capacity to metastasize. 10% = familiar BRCA1 or BRCA2
follicular phase is dependent on what
FSH
what happens to CL at end of luteal phase
degenerates and P and E drop
the endometrium changes
endometrium def
mucosal layer of the uterus
-grows during follicular phase (2 phases: follicular and luteal)
portions of fallopian ducts
- fimbriae (many mucosal layers of the oviduct projecting externally. epithelial lining)
- ampulla (longer portion. foliated, ombligated mucosa. labyrinth in the lumen). fertilization = there
- corona radiata with oocyte inside being pushed by ciliated cells of epith of mucosa in fimbriae and ampulla*
what surrounds the mucosa with ciliated epith in the ampulla of Fall tube
2 layers of SM cells
- inner circular
- outer longitudinal
portions of oviduct after ampulla
- isthmus
- intramural interstitial part
histology of oviduct fimbriae
- epith with BM
- under BM, stroma rich in CT cells and a large number of vascular structures
- erectile tissue like
important thing about stroma of WHOLE oviduct
stromal cells can develop into situal cells, meaning they can be competent to accept the oocyte at fertilization (site of ectopic pregnancy) + very vascularized so place where it works
epithelium of fimbriae
ciliated (mostly) with motion towards uterus and non ciliated cells secretory cells
CAN’T DIFF ON LM, ONLY ON EM
ampulla on histo
- muscular layer outside
- lot of folds, very foliated
- ciliated (mostly) with motion towards uterus and non ciliated cells secretory cells
common point of ciliated and non ciliated secretory cells of oviduct epith
can change into the other type, share same origin.
- estrogen (made in follicular stage) tends to make these cells ciliated
- more ciliated cells in follicular phase
- less ciliated cells in luteal phase
what secretory non ciliated cells of oviduct epith do
produce proteins and factors promoting fertilization
-one protein is oviductin. imp in stim oocyte to receive sperm
isthmus vs ampulla of oviduct mucosa
- isthmus not as foliated
- isthmus = ridges only
- in the isthmus, MORE secretory cells than ciliated
- in ampulla, MORE ciliated than secretory
- isthmus has inner circular and outer longit layers of SM like ampulla
intramular oviduct charact
- embedded in myometrium of uterus
- mucosa continuous with endometrium of uterus
portions of uterus
- fundus (roof)
- body (lateral portions)
- isthmus
- cervix
(imp) blood supply to uterus
uterine a. has branches penetrating in myometrium (muscular layer of uterus). note: the endometrium = mucosal layer of uterus facing lumen
branchings of the uterine a
- arcuate arteries enter the myometrium
- split in elbows of radial aa also in the myometrium. these split into 2 kinds of branches: coiled a. and other branch
- coiled a. supplies superficial part of endometrium
- other branch supplies bottom part of endometrium
endometrium structure
- epithelium
- BM
- stratum functionalis (superficial, spongy zone)
- stratum basale (basal zone)
endo epith charact
mostly secretory and some ciliated cells
endo stratum functionalis charact
- stroma
- coiled glands with their base in the stratum basale and end in the endo epith
- CT and residual cells
- irrigated by branches and small capillaries from the spiral coiled arteries
- lost during menstruation
stratum basale charact
- denser area
- contains ends, bases of uterine glands
- myometrium (80% of uterine thickness) is underneath
- remains during menstruations and repopulates the stratum functionalis by using the cells of the glands
layer of uterus below myometrium
serosa, similar to that of peritoneal cavity
myometrium contains how many layers
4 layers of diff SM
how uterine mass varies during pregnancy
myometrium increases x24. so mass goes x24. cells of the myometrium hypertrophy
early follicular phase (day 4) endometrium
- stratum functionalis (superficial layer) was lost during menses
- FSH starts effect
- remaining cells of uterine glands (in stratum basale) repopulate the epith of endometrium by mitosis
- stromal cells actively dividing
- no secretory activity in the glands
end of follicular phase (day 14), beginning of luteal phase endometrium
- endometrium done being repopulated
- glands now more tortuous and coiled
- branches of coiled arteries supply the whole endometrium
start of luteal phase endo
- LH being released
- secretion of P and E (P makes the endo secretory)
- glands actively secreting glycogen broviding nutrients to egg if implants
end of luteal phase endometrium
- no fertilization, CL regresses, less E and P
- coiled arteries contract bc of that (media of aa contracts), ischemia, lack of O2 in endo
- several phases of contractions and relaxations, persistent ischemia
- aa eventually open and everything will break. lot of RBCs form lakes of blood within the endo
- endo becomes shorter
menstrual phase endo
- coiled artery opens + get release of RBCs in endo
- epithelium break and superficial part is released
- get profuse bleeding
- back to early follicular phase
uterine glands in the diff phases
- follicular = become tortuous
- luteal = become saccular + lot of secretory activity in the lumen
- also, lakes of blood in end of luteal phase (but not related to glands)
what’s inside of the isthmus of the uterus
cervical canal with internal and external os. epith different from endo
appearance of cervical canal epith on histo
has projections going inwards, gland like, called plica palmate. truly are glands at the bottom of the cervical canal
name of cysts forming in glands of cervix
Nabothian cyst. can become large and occlude the cervical canal
name of bottom part of cervix protruding in vagina
portio vaginalis
portio vaginalis histo
stratified columnar epith
histo of the cervix
- plica palmatae (mucosa projections)
- glands in bottom of canal
- secretory epith with mucous secreting cells
what glands in cervix do
plaque of mucous that stops penetration of sperm during the luteal phase
portio vaginalis clinical relevance
- if epith infected with HPV, may lead to cervical cancer (not the case for vaginal epith)
- so cervical cancer related to squamous stratified epith
vagina histo
- squamous stratified epith
- BM
- LP with bit of CT
- deeper, have combination of CT and SM cells
