Topic 17: Reproductive System - Female Ovarian Follicles and Follicular Development Flashcards
What are the 6 follicle stages?
- Primordial follicle
- Primary follicle
- Secondary follicle
- Vesicular follicle
- Corpus luteum
- Corpus albicans
What is the primordial follicle? (2)
- in ovary at birth
- 1° oocyte surrounded by single layer of flat follicular cells
What is the primary follicle? (2)
- the single layer becomes cuboidal
- now called granulosa cells; proliferate to become stratified
What do primary follicles secrete?
- zona pellucida around oocyte
What cells form in primary follicle?
- theca cells form from surrounding tissue
Which stage can ovaries reach anytime from birth to menopause?
- primary follicle
What occurs in the secondary follicle stage?
- at puberty, ovarian cycle begins
- under the influence of rising FSH
The secondary follicle is under the influence of rising FSH. Because of this, what happens?
1) Granulosa cells proliferate more and start to secrete fluid (accumulates between cells)
2) estrogen secretion begins
Where is the vesicular follicle found?
- on surface of ovary
what do the fluid filled spaces in the vesicular follicle stage unite to form?
antrum
In the vesicular follicle stage, what are the granulosa cells that still surround oocytes?
corona radiata
In the vesicular follicle stage, what is still being secreted? What does it cause?
- estrogen
- estrogen triggers release of LH
In the vesicular stage, what does secretion of LH cause? (2)
- completion of meiosis I
- enters meiosis II and arrests in metaphase II - Ovulation
What occurs in ovulation?
- release of 2° oocyte from follicle into peritoneal cavity
What is the corpus luteum?
- follicle that remains after ovulation
