Microanat of Cycle Flashcards
3 general parts of an ovary
Surface epithelium
Cortex
Medulla
2 major functions of the ovaries
Producing ova (oogenesis) Secreting hormones (steroidgenesis)
3 stages in non-cyclical follicular development
Primordial germ cells
Primordial follicles
Primary follicles
Starts during embryonic development, to menopause(does not depend on gonadotropin)
Where does the cyclical stage of follicular development start?
The transition between primary and secondary follicle
Requires gonadotropin
From sexual maturity to menopause
NO - between primary uni-laminar and primary multi-laminar
Primordial follicle
Simple structure
Primary oocyte arrested in 1st meiotic division
Flattened follicular cells
Surrounded by stromal cells
Stromal cells will become…
Theca interna and theca externa
Primary follicle (uni-laminar)
Cells surrounding the cell are now cuboidal (called granulosa cells)
Basal lamina separattes granulosa cells and oocyte from stromal vasculature (follicles are avascular)
Primary follicle (multi-laminar)
Granulosa cells have now stratified
Granulosa cells send processes through zona pellucida to oocyte cytoplasm (metabolically and electrically coupled)
Function of
- Theca interna
- Theca externa
- Estrogen production
2. Smooth muscle
Zona Reaction
Acrosome reaction (sperm burrows through zona pellucida)
Rapid depolarization of oolemma
Cortical granules fuse with oolema and spill proteases
Proteases cross-link and harden proteins on zona pellucida
Blocks polyspermy
Secondary follicle
First sign of antrum (fluid from granulosa cells)
Role of antral fluid
Made by the granulosa cells
Key roles in follicular growth, oocyte maturation and ovulation
Graafian follicle
Zona granulosa now at the periphery of the follicle
Cumulus oophorus bridge
Corona radiata
Theca interna and externa cells
Cumulus oophorus
Bridge between the oocyte and the granulosa cells
What 3 things are released in ovulation
Oocyte
Surrounding zona pellucida
Corona radiata (nutrients)
After ovulation what do
1. Zona granulosa
2. Theca interna
cells become?
- Granulosa lutein cells
- Theca lutein cells
Together they produce estrogen and progesterone* to maintain uterine lining until implantation
Role of hCG
Causes the corpus luteum to continue to secrete estrogen and progesterone to maintain the uterine wall
Taken over by the placenta at 8-12 weeks
2 layers of the uterus
Endometrium
Myometrium
2 layers of the endometrium
Functional layer
Basal layer
Asherman’s
Damage to the basal layer of the endometrium
Adhesions between the walls of the uterus and you cannot regenerate the functional layer
Adenomyosis
When the glands in the endometrium grow into the myometrium
Can be very painful
What substance do the endometrial glands make?
Glycogen
