Ova Manufacture Flashcards
What are the 2 million reproductive stem cells of the ovaries?
Oogonia (oogonium)
What process do Oogonia go through?
Why?
Mitosis
Oogonia are diploid cells that must create identical copies
What are the cells that are created from Oogonia?
Primary Oocyte (Diploid cells)
What covers primary oocytes?
A layer of tightly attached simple squamous epithelium.
Called follicular cells
What is the entire complex of primary oocytes and follicular cells referred to as?
Primordial Follicle
What process do primary oocytes go through (before puberty)?
Meiosis I
Do not complete process until after puberty
What is the complex created by primary oocytes?
Primary Follicles
After puberty, how often does ovulation occur?
Approximately every 28 days.
What begins the process of ovulation after puberty?
FSH is released by the pituitary gland in response to GnRH released by the hypothalamus.
How is a primary follicle selected for development?
One primary follicle, chosen randomly, reacts to FSH
What does FSH do to the “chosen” primary follicle?
- Follicular cells grow and develop a layer of cells around the egg:
Thecal cells
- secrete follicular fluid
What is follicular fluid?
Straw colored fluid, rich in estrogens that fills the are between follicular cells and developing egg in space:
Antrum
What is the thick membrane that develops around the ova in response to FSH?
Zona Pellucida
Once a primary oocyte completes process of meiosis I, what happens?
Division of cytoplasm occurs unevenly.
Creates two haploid cells:
- First Polar Body
- Secondary Oocyte
What happens to First Polar Body cells?
Do not receive sufficient cytoplasm and eventually die and disintegrate
What happens to the antrum of secondary follicles?
Follicular cells continue to release Follicular fluid until the follicular cells balloon outward.
Graafian cells result
What does estrogen do?
- Causes anterior pituitary gland to release L.H.
- Causes endometrial lining of uterus to grow and mature
- Inhibits release of FSH
What is the “burst of L.H.”
Sudden release of L.H. in response to estrogen
What does L.H. cause?
- Increase in body temperature
- The rupture of graafian follicle
Once the graafian follicle ruptures, what happens?
The egg and follicular fluid are released to the fallopian tubes
Why does estrogen affect the endometrial lining?
Preps it for embryo implantation
Why does L.H. prevent the release of FSH?
Allows the body to allow fertilization of egg cell before developing another
After ovulation, does the body have a main source of estrogen?
No
What hormone is released to accomodate for the loss of estrogen after ovulation?
Progesterone is released by Corpus Luteum
