Reproduction - female tract Flashcards
What attaches to the ovary?
- Broad ligament
- Utero-ovarian ligament
- suspensory ligament attaches to pelvic wall
Describe the structure of the ovary
- Covered by single layer of modified mesothelium
- tunica albuginea - poorly defined connective tissue
- stroma is divided into cortex and medulla
Cortex = Ovarian follicles, arranged in whorls/storiform pattern
Medulla = Loose fibroelastic tissue with blood vessels, lymphatics and nerves
Describe the stages of egg development in the ovary
- Primordial follicles - periphery of cortex (primary oocyte)
- Primary follicles - cyclic, oocyte forms and ZP forms around it
- Secondary follicles - antrum forms,
- Mature (Graafian) follicles - ovum surrounded by thick ZP
- theca interna, and theca externa (approx 400,000 at birth, only about 400 ever mature further) - Corpus luteum - secretes progesterone and oestrogen
(they either regress if pregnancy does not occur or grow)
What does the fallopian tube do? What are the 4 segments?
Runs throughout the length of the broad ligament
-Transports ovum to uterus (ampulla of fallopian tube, or uterine tube), this is where fertilisation occurs
4 segments
- Intramural - inside uterine wall
- Isthmus - 2-3cm thick wall
- Ampulla - expanded area
- Infundibulum - trumpet shaped opening to peritoneum, has FIMBRIAE
mucosa - has plicae folds, 3 cell types - secretory, ciliated and intercalated
- Muscularis (inner circular layer and outer longitudual)
- Serosa (connective tissue covered by mesothelium)
layers of the uterus
- Endometrium - glands proliferate during proliferative stage of menstral cycle
- Myometrium - thick muscular wall (inner longitudial, middle circular, outer longitudial)
- Serosa -
Describe layers of vagina
- Mucosa, non keratinising, strat squamous, elastic fibres, rich vascular supply
- Muscular wall (inner longitudial, middle circular, outer longitudial)
- Adventida
Lining of labia majora
Keratinising stratified squamous
Labia minora
Mostly non-keratinising stratified squamous
Describe the stages of oogenesis
metosis division and 2 meiotic
- In early development numerous mitotic divisions occur, stops around 7 months - divides into PRIMARY OOCYTE (diploid)
- first Meiotic division occurs in a featus up to prophase I - then it is in a state of meiotic arrest
- After puberty division produces first polar body and SECONDARY OOCYTE (possesses half chromosomes but all nutrients and cytoplasm)
- After ovulation and fertilisation the second meiotic division occurs in the fallopian tube - this produces OVUM (haploid) and secondary polar body
What is the role of granulosa cells?
Secretes estrogen
- small amounts of progesterone just before ovulation and INHIBIN
- Theca cells also synthesize estrogen
Why does the antrum form?
Due to fluid secretion of the granulosa cells
What does estrogen affect mucus?
Mucus is abundent, clear and water, this means that sperm can move through it more easily
-during ovulation
What does progestrogen affect mucus?
Mucus is thick and sticky
-This forms a ‘plug’ that prevents bacteria from entering forming protection if fertilization has occurred
(this is used as a form of contraception)
What causes menstruation?
The corpus luteum degenerates if fertilisation has not occurred, this means that there is a reduction in estrogen and progesterne - this is what causes menstruation
What occurs during menstruation?
a. Constriction of blood vessels
b. Reduction of Oxygen and nutrients
c. Entire layer except thin underlying layer
d. Smooth muscle undergoes rhythmic contractions
- these contractions are mediated by prostaglandins that are produced in response to low pro and est (can cause cramps, and affect other areas of the body = nausea, vomiting, headaches)
e. Blood vessels then dilate - causes hemorrhage and bleeding through the weakened capillaries