what part of the ovary contains the developing follicles?
cortex
where is the cortex located in the mare?
centrally
what is the edge of the cortex in the center of the ovary in the mare?
ovulation fossa
what is the tissue between the follicles referred to as?
stroma
what are the characteristics of the stromal cells
- fibroblast-like
2. with lipid droplets
what is the CT around the outer edge of the cortex
tunica albuginea
what is the covering over the ovary?
tunica serosa ( AKA mesovarium)
what kind of epithelium does the tunica serosa have?
simplie cuboidal (that gets more squamous with age)
what contains the blood vessels of the ovary?
ovarian medulla
what are the system of channels in the ovary that can for cysts and tumors?
rete ovarii
what are the stem cells that divide mitoically until birth, that give rise to primary oocytes (which become arrested in meiotic prophase I)
oogonia
when stimulated to divide, what type of division do primary oocytes complete/become?
- meiosis I
2. form secondary oocyte and the 1st polar body
when is the secondary oocyte formed in most species?
just prior to ovulation
what type of oocye do the mare and dog ovulate?
primary oocyte
regardless of stage of development of the follicle, all obserable follicles on slides of postnatal ovaries contain what kind of oocyte?
primary oocyte
when does the secondary ooctye undergo the 2nd meiotic division?
right after fertilization
what is formed by the secondary oocyte after meiosis II?
- ovum
2. 2nd polar body
female germ cells in most animals are arrested at what stage of development until the time of ovulation??
primary oocyte
what surrounds the oocyte inside the follicle, that is a capsule-like structure
zona pellucida
what is the layer of epithelial cells around the oocyte?
granulosa cells
what is the zona pellucida made of ?
a think glycoprotein layer
what secretes the zona pellucida?
both the oocyte and granulosa cells
what surrounds the follicular epithelial cells (granulosa cells)
- basement membrane
2. theca (interna/externa)
what are the stages of the follicle?
- primodial
- primary
- secondary
4 tertiary (Graafian)
what follicle has the oocyte surrounded by a single layer of squamous cells
primordial follicles
what type of follicle has the oocyte surrounded by cuboidal granulosa cells?
primary follicle
what type of follicle do small pockets of follicular fluid appear between granulosa cells?
secondary follicle
what type of follicle has one large fluid-filled cavity (antrum) with a layer of granulosa cells around the periphery (stratum granulosum)
tertiary follicle
in advanced follicles, the granulosa cells are divided into what specific areas? (most interior to exterior)
- corona radiata
- cumulus oophorus (surrounds oocyte)
- stratum granulosum
what are the follicles that are degenerating?
atretic follicles
can a follicle become atretic at any stage?
yes
what cells are often ovulated with the oocyte?
cumulus oophorus
what cells are formed in the dog and cat from theca interna cells, which persist?
interstitial cells
what are the two general phases of the ovarian cycle?
follicular and luteal
what is the transient endocrine gland derived from an ovulated follicle?
corpus luteum
what does the CL produce?
progesterone
what hormone plays a large role in the establishment and maintenance of pregnancy?
progesterone
CL regression is an example of:
apoptosis
what hormone is involved in the regression of the CL?
PGF2alpha
what stage is the CL degenerating/regressing?
follicular stage
what stage is the follicle maturing toward ovulation?
follicular stage
what stage is estrogen being produced by the granulosa cells in response to FSH?
follicular stage
late in what stage does the LH surge trigger ovulation?
follicular stage
what stage is the endometrium in the uterus proliferating?
follicular stage
theca cells have what kind of receptors?
LH receptors
what do theca cells produce?
androgens
what type of receptors do granulosa cells have initially?
FSH receptors
what do granulosa cells produce?
estrogens
estrogen has what kind of feedback on granulosa cells?
positive
granulosa cells later develop what kind of receptors?
LH receptors
rising estrogen levels during the follicular phase stimulates what?
release of LH from pituitary (causes LH surge)
what does the LH surge stimulate?
- primary oocyte to complete meiosis I
- starts process of ovulation
- induces formation of CL
what cells form the CL?
granulosa and theca cells
in what phase is P4 produces by the CL
luteal phase
in what phase are there several waves of follicles that become atretic?
luteal phase
in what phase are the uterine glands secreting?
luteal phase
LH secretion maintains what?
CL
P4 stimulates development of what?
uterine endometrium
P4 from the CL inhibit what?
FSH and LH release
what CL degenerates each cycle that there is no implantation?
CL cyclicum
what CL persists if there is implantation?
CL of pregnancy
what is the CL gradually replace by that is a CT scar?
corpus albicans
P4 has what type of feedback on LH secretion?
negative