Highison--Female Reproduction Flashcards
From the outside to the inside, what are the main layers of a woman’s ovary?
Germinal Epithelium
Tunica Albuginea
Cortex
Medulla
What makes the germinal epithelium?
This is sort of a peritoneal covering on the outside of the ovary–>it is made up of mesothelial cells.
What makes up the tunic albuginea?
This is a CT band that is found in both the ovaries & testes.
What are the 2 main things that the endocrine portion of the ovary secretes?
Estrogen
Progesterone
Where are the arteries & veins found in the ovary?
in the medulla! this is also where the hormones travel
Where are the follicles found in the ovary? What are the different levels?
in the cortex! Youngest: Primordial Follicles Growing Follicles Preovulatory Follices Corpus Luteum Oldest: Corpus Albicans
When is a follicular cell considered a granulosa cell?
once it starts producing hormones…
Where is the primary oocyte from? Where are the follicular cells from?
Primary Oocyte–>from the secondary yolk sac, producing from Meiosis I
Follicular cells–>from the ovary
Describe the characteristics of the primordial follicle.
Outside–>Inside
Basal Lamina
Squamous follicular or Granulosa cells
Primary Oocyte
After a primordial follicle changes to a __________, what are its characteristics?
Primary Follicle-->unilayered Outside-->Inside Basal Lamina cuboidal follicular cells Zona pellucida starts to form primary oocyte
What produces the zona pellucida?
the primary oocyte!
The primary follicle that is unilayered then forms ________, what are its characteristics?
Primary Follicle Multilayered Outside-->Inside Theca Externa Cells: CT Theca Interna Cells: look nice & plump Basal Lamina multilayered cuboidal follicular cells Zona pellucida primary oocyte
At the point of the primary follicle multilayered forms do you still have a primary oocyte or is it a secondary oocyte?
Still a primary oocyte!! : )
What are the 3 glycoproteins that make up the zona pellucida?
ZP1, ZP2, ZP3
What prevents early meiosis I prophase I completion?
oocyte maturation inhibitor (OMI)
this is secreted from the surrounding follicular cell. They have a process that pierces thru the ZP & gets to the primary oocyte. thru a gap jcn it communicates & gives the OMI.
The egg must complete meiosis I prophase I before ovulation. With all of this OMI hanging around…how does it achieve that?
there is a complex formed by cdc2-cyclin B that is called MPF: maturation promoting factor.
This goes into the nucleus and completes the thing. It gets into the nucleus by breaking down the nuclear envelope, a process called germinal vesicle breakdown.
When MPF gets into the nucleus via germinal vesicle breakdown, what else happens?
the formation of the first polar body, which then rests in the perivitelline space.
Where do gap junctions exist in a follicle?
b/w the follicular cells that make up the corona radiata. They also exist b/w the cell process of the follicular cell & the primary oocyte.
Where is the perivitelline space located?
b/w the primary oocyte & the ZP
What happens to the structure of the follicle @ fertilization?
through Ca++ release, the cortical granules (little protrusions off of the secondary oocyte)…release proteases that act on the ZP.
ZP2 glycoprotein changes conformation…
ZP3 glycoprotein has its carbs removed…
This makes it impossible for another sperm to penetrate
When the theca interna cells are super rounded up in shape…do you have follicular cells or granulosa cells?
granulosa cells!
In a secondary follicle, what are the theca externa cells all about?
These are stromal cells on the very outside & they are mainly made of CT.
In a secondary follicle, what are the theca interna cells all about?
These are inside of the theca externa cells & they are endocrine cells that produce androgens.
What’s the deal w/ the antrums in the secondary follicle?
these are formed by the call-exner bodies that produce the antrum.
the antrums push out the primary oocyte.
the antrum is filled w/ hyaluronate, steroids, growth factors, gonadotropins
What are call-exner bodies?
these are organizing follicular cells that form the antrum.
Where are the blood vessels found that supply the follicle?
in the layer with the theca interna cells
At what point do you have a corona radiata?
once the antrum gets super big, pushes the primary oocyte to one side & you are a Graafian follicle.
then the corona radiata surround the ZP
When you have a Graafian follicle, do you have CT?
yes, in the outer layer of the theca externa cells.
What is the cumulus oophorus?
a mass of epithelial granulosa cells surrounding the oocyte in the maturing ovarian follicle.
In a maturing follicle if the cumulus oophorus is like the golf tee, what is the golfball?
Golfball: primary oocyte
In the primary or secondary follicle, where is the estradiol secreted from?
from the follicular or granulosa cells
Explain the entire process, including the hormones that are involved, in secreting estradiol from follicular cells.
Cholesterol from the blood goes into the theca interna cells.
LH from the blood binds LH receptors on the theca interna cells.
Androstenedione is made in the theca interna cells & gets over to the follicular cells.
FSH from the blood binds the FSH receptor on the follicular/granulosa cells. This causes the formation of estradiol & its secretion.
Explain the types of receptors on follicular/granulosa cells.
Early on: only FSH receptors Later On (Graafian follicle): FSH & LH receptors; the importance of the LH receptors is that this allows for the lutenization of the ruptured follicle after ovulation.
Ovulation occurs on which day? As what type of cell?
on day 14
as a secondary oocyte.
Note: a polar body will be seen.
What types of cells is the corona radiata composed of?
specialized follicular cells
What does angiogenesis have to do with ovulation?
angiogenesis, the proliferation of more blood vessels, takes place in the theca interna
After ovulation, what is released? What are the layers?
Outside–>Inside
Corona Radiata
ZP
2ndry oocyte & polar body
Which tissue layers will be left behind after ovulation?
Outside-->inside tunica externa (CT) tunica interna (tons of blood vessels) basement membrane granulosa cells
Which position does the follicle need to be in before ovulation? Which layers must it break through?
must be located near the surface
theca externa
tunica albuginea
surface epithelium
How does the follicle miraculously burst through the final layers?
LH surge
proteases are released from fibroblasts
they degrade the collagen fibers of the theca externa & tunica albuginea