female repro: ovaries Flashcards
1
Q
general organization
A
- mesothelium (germinal epithelium)
- CT capsule (tunica albuginea)
- Cortex (parenchyma) with ovarian follicales and interstitial tissue (stroma)
- medulla
2
Q
what is found in the ovarian follicle in the cortex?
A
- follicles: primordial, primary, secondary
- gametogenic cells: primary and secondary oocyte
- supporting cells
3
Q
stages of folliculogenesis
A
- primordial follicles
- primary follicles form
- vesicular (secondary) follicle
- mature vesicular follicle
- ruptured follicle
- corpus luteum early and mature
4
Q
medulla
A
-coiled blood vessels
-nerves
-fibroelastic CT
-
5
Q
primordial follicles
A
- single layer, flattened follicle cells
- 600 to 800k at birth
- primary oocyte, meiosis 1 is not complete, it is stuck in prophase of meiosis 1
- duplicated chromosomes (4n, post crossing over)
- balbioni bodies: golgi membranes
- annulate lamellae: stacked nuclear membranes
6
Q
primary early follicle
A
- single layer, cuboidal follicle, no longer flattened
- primary oocyte
- zona pellucida appears
- prominent basal lamina
- stromal cells begin to condense around follicle
7
Q
primary (late, multilaminar) follicle
A
- obvious growth of oocyte
- several layers of follicular cells called granulosa cells
- possibly pseudostratified
- zona pellucida well developed
- perforated by microvilli from oocyte and granulosa cells
- gap junctions between microvilli
8
Q
secondary antral follicles
A
- appearance of follicular fluid
- theca interna and externa develop (steroidogenic cells and myofibroblasts, respectively)
- elevated estrogen levels in part due to the concentration by sex steroid binding globulin
9
Q
theca interna
A
synthesize androgens via LH stimulation
-
10
Q
what does rising estrogen levels stimulate
A
-endometrial gland proliferation and at mid cycle, LH surge
11
Q
theca externa
A
- cells will differentiate into myofibroblast like cells
- LH responsive
- contract during ovulation
12
Q
mature (graafian) follicle
A
- secondary oocyte (meiosis 1 has been completed)
- unequal cytokinesis gives rise to the first polar body
- haploid (but still 2n DNA - sister chromatids will separate in meisosi 2)
- ovulation will occur shortly after surge of LH
- contaction of theca externa myofibroblasts expel the ovum
13
Q
corpus luteum (yellow body)
A
- breakdown of follicle basement membrane
- ingrowth of blood vessels
- proliferation and infolding of GC’s and theca interna (TI) appears brain like
- differentiation of theca interna cells and granulosa cells into : theca lutein cells (smaller and darker) and granulosa lutein cells (both stimulated by LH)
14
Q
rising progesterone levels with stimulate what
A
-endometrial gland secretion
15
Q
corpus albicans (white body)
A
- form each cycle and following pregnancy
- after 10d degeneration leads to drop in progesterone
- corpus luteum cells die and replaces by collagenous scar
- few cells giving a homogenous eosinophilia
- appears cloud-like
