Female Reproductive Tract Flashcards
Which way do the ovaries face? (Which side of Broad Ligament would you find them?)
They face posteriorly.
Give a brief rundown of Follicular development in the ovaries.
Primordial Follicle -> Early Primary Follicle -> Secondary Follicle -> Mature Graafian Follicle -> Oocyte released -> Corpus Hemorrhagicum -> Corpus Luteum -> Corpus Albicans
Describe the cortex and medulla of the Ovaries.
Cortex: contains follicles and tunica albuginea. Covered in simple cuboidal germinal epithelium
Medulla: contains loose CT which houses smooth muscles and neurovasculature + lymphatics.
How many of the 2-5 million primary oocytes are left at time of birth? How many mature ova are produced throughout life?
400-600 thousand. The rest are gone from atresia.
400-500 fully mature ova are produced.
Which of the three stages of Follicle development are histologically identifiable?
Primordial
Primary/Secondary (Antral)
Mature/Graafian
What hormone stimulates growth of the primary oocyte in the Primordial Follicle?
FSH
This growth makes the Primordial Follicle transition into Primary Follicle (flattened layer of follicular cells become simple cuboidal)
What does the Primary Follicle develop that indicates it has developed into the next stage (Multilaminar Follicle stage)?
Clearly defined Zona Pellucida.
Contains glycoproteins, most important of which is ZP-3, the spermatozoa-binding receptor.
What structure helps identify Secondary/Antral Follicles?
Clearly defined Antrum
Thecal cells
- Interna: vascular layer of secretory cells
- Externa: CT layer
At this point, 10-14 days left to mature follicle.
What are the hormones produced and which cells are they produced by in the Secondary Follicles? (Ovarian Steroidogenesis)
Thecal Cells and Stroma produce androgens, which pass through follicular basement membrane to Granulosa Cells, where the androgens are used as a substrate for Estrogen production.
During what phase is Estrogen production at its highest?
Proliferative phase.
How do you identify a Mature/Graafian Follicle?
Antrum becomes significantly larger
Granulosa cells around antrum form Membrane Granulosa
Follicular cells form Cumulus Oophorus and Corona radiata precursor
What occurs during the Graafian Follicle state due to LH surge?
Meiosis is resumed. Secondary oocyte and first polar body formed.
Enter second meiotic division and halt at metaphase until fertilization.
Describe the steps of Ovulation.
- Graafian follicle bulges on surface of ovary
- Surface layers of ovary weaken and rupture
- Ovum released from follicle
- Ovum is drawn into the oviduct by fimbriae
- Fertilization occurs in ampulla of oviduct, causing completion of Meiosis II
Describe the overall process of Fertilization and Implantation.
Day 0
- Fertilization in ampulla
- Zygote is formed
Day 1
- First cleavage is formed on the way down the Ampulla
Day 2
- Zygote has entered 2-cell stage
Day 3-4
- 4-cell stage
- 8-cell uncompacted Morula formed
Day 4
- 8-Cell Morula compacted
Day 5
- Early blastocyst formed
Day 6-7
- Late-stage blastocyst formed (Hatching)
Day 8-9
- Blastocyst successfully implants in endometrial wall.
What is the Corpus Luteum?
The leftover follicle following ovulation.
- granulosa cells -> granulosa lutein cells
- Theca Interna -> Theca lutein cells
- membrane granulosa thrown into folds
Function: secrete progesterone and estrogen
Lutiein cells invaded by capillaries and CT
What is the fate of the Corpus Luteum with/without fertilization?
No Fertilization: Corpus luteum of Menstruation forms, lasts 14 days, and then degenerates to form corpus albicans.
Fertilization: Corpus luteum of Pregnancy forms, lasts 6 months, and gradually forms a corpus albicans after birth.
What do the lutein cells of Corpus Luteum secrete during pregnancy/childbirth?
Relaxin
- Pregnancy: mediate hemodynamic changes (e.g. cardiac output)
- Childbirth: promotes dilation of cervix
What is follicular atresia?
Several follicles develop per cycle, but only one matures. The rest are Atretic Follicles, which are degenerated follicles.
These cells (and their ovum) are resorbed and replaced by connective tissue to form a scar.
Note the remnant of the zona pellucida in Atretic Follicles
What is the Corpus Albicans?
Basically a dead Corpus Luteum. It is essentially an acellular scar (invaded with collagenous fibers).
What are the 4 segments of the Uterine Tubes (Oviducts/Fallopian Tubes)?
Infundibulum
Ampulla
Isthmus
Intramural
Total = 12 cm
Describe the layer organization of the Uterine Tubes.
3 Layers
Mucosa (Note Fimbriae of the epithelium)
Muscularis
Serosa
Note similarity to ureter
What are two distinct cell types of the Uterine Ampulla?
Ciliated Cells (Movement of ovum)
Peg Cells (Secretory cells)
Note: ID Peg cells by their long nuclei
What are the 2 anatomical regions of the Uterus?
Body (upper part = fundus)
Cervix
What are the layers of the Uterine Body?
Perimetrium (Serosa)
Myometrium (3 thick smooth muscle layers)
Endometrium (Mucosa)
What are identifying characteristics of the Endometrium?
- presence of tubular glands with ciliated secretory cells (produce glycogen rich secretions)
- straight and spiral arteries
- proliferates/degenerates in menstrual cycle
What are the two layers of the Endothelium?
Stratum Functionale (Layer that proliferates/degenerates)
Stratum Basale (Regenerator)
Which layers of the Endometrium contain which artery types?
Straight - Basale only
Spiral (coiled) - Basale and Functionale
- break down during menstruation
What hormone drives the Proliferative phase of the menstrual cycle? The Secretory phase?
Proliferative - Estrogen
Secretory - Progesterone
Describe the Proliferative phase.
Day 4- 14 of menstrual cycle.
Endometrium thickens
- glands are straight and narrow
- coiled arteries do not pass lower half of Functionale layer
Describe the Secretory phase.
Lasts 12-14 days,
- glycogen accumulates in epithelial cells
- nutrient secretions accumulate in glands (are now tortuous and sacculated)
- coiled arteries reach superficial portion of Funtionale
Describe the Menstrual phase.
days 1-4: Stratum Functionale and blood are lost
day 4: epithelial cells glide out from glands to restore surface epithelium
- spiral arteries close off and suppy Basale
- patches of tissue separate from the endometrium; blood will flow from open ends of veins.
What is the Transformation Zone?
Area where the endocervix and ectocervix meet.
It is the site of:
- Metaplasia (Transformation of one tissue into another)
- Dysplasia (Abnormal tissue development)
- Cervical Cancer
Describe the Endo/Ectocervix.
Endocervix - fibromuscular; lined by simple columnar epithelium containing ciliated cells, mucus-producing cells, and several tubular glands. (Lowest portion of uterus)
Ectocervix - lined by non-keratinized stratified squamous epithelium. (Outer portion of cervix that protrudes into vagina)
What is consistently happening in the Endocervix? Why?
Secretory activities of the glands and the consistency of the mucus will change to accomodate potential pregnancy.
- 10x increase in mucus secretion when ovulating, with thinner mucus to facilitate sperm migration.
What is the main cause of Cervical Cancer?
HPV (Human Papilloma Virus)
What cytological differences will you see in a Pap smear with normal and abnormal cells?
Normal: Small nuclei with abundant cytoplasm
Abnormal: Large nuclei with minimal cytoplasm
What is the opening of the Cervix into the vagina called?
The Os.
What sort of epithelium would you find lining the Vagina?
Non-keratinized stratified squamous epitheilum with a lot of transverse folds (Rugae)
Where do the secretions of the Vagina come from?
From the Cervix! Lamina Propria of the Vagina does NOT contain any glands.
