Repro 5 Female Anatomy Flashcards
How are the oocytes stored?
In the follicles in the outer cortex of the ovaries (1 oocyte per follicle). Each oocyte is surrounded by stromal cells (follicular cells) forming primordial follicles (pale staining nucleus)
Where do oocytes originate from?
Outside the ovary from the primordial germ cells that colonise the ovary during early embryonic development
What happens to the primordial germ cells in the ovary?
Divide by mitosis to form oogonia which develop into oocytes by undergoing meiosis
When does meiosis of oocyte complete?
After fertilisation - if not fertilised, meiosis is not completed
At what stage of division does the oocyte halt meiosis?
Diplotene phase of 1st meiotic prophase until just before ovulation.
How many oocytes mature each month?
Several begin to develop each month but generally only one (sometimes 2) develop to primary oocytes just before ovulation and are released.
What happens to the primary ooctye at ovulation?
The first meiotic division completes to form a haploid secondary oocyte and a polar body
How many follicles persist at puberty and what happens to the rest?
Approx 400,000
Many follicles undergo degeneration (atresia) in the fatal and postnatal ovary
Approximately how many oocytes will develop fully and be released in menstruation of a woman’s life?
400
What are the 2 different populations of follicles?
Reserve pool of non-gorwing follicles (larger) and a smaller pool of growing follicles, derived periodically from the former group.
What happens to the reserve pool of follicles?
Constantly depleted as no new follicles are made after birth therefore stores are exhausted around the age of 50-55
What is folliculogenesis?
Entry of follicles into the growth phase and their subsequent development
What transformations occur to form a primary follicle from a primordial follicle?
The single layer of flattened follicular cells transform into a layer of cuboidal granulosa cells
Glycoproteins secreted by the granulosa cells that contribute to the formation of the zona pellucida surrounding the oocyte appear at this time and form a thick amorphous layer as the follicle grows
How are secondary pre-antral follicles formed?
Granulosa cells form multiple layers and transformation of the surrounding stromal layers to theca folliculi which comprises the oestrogen secreting theca interna and a fibrous theca externa
What signals the formation of a tertiary or astral follicle?
Appearance of a fluid-filled cavity - antrum. These follicles enlarge by an increase in the fluid volume and proliferation of the granulosa and thecal cells
What are Graafian and ovulatory follicles?
Graafian follicles are large antral follicles and only one of the most advanced of these will become the ovulatory follicle
What happens to the ovum at ovulation?
The follicle ruptures to release the ovum, the granulosa and theca interna cell show structural (and functional) transformation. The entire mass of the tissue becomes highly vascularised via the growth and infiltration of blood vessels from the surrounding tissue
What is the appearance of the granulosa cells in the corpus luteum?
undergo hypertrophy and form a thick and folded layer of granulosa lutein cells which have a spherical nucleus and pale stained vacuolated cytoplasm containing numerous lipid droplets
What happens to the internal thecal cells in the corpus luteum?
Transformed into theca lutein cells and occupy depressions formed by the granulosa lutein cells accompanied by blood vessels.
What is in the central cavity of the corpus luteum?
Undifferentiated connective tissue
From what are ovarian cysts derived?
Follicles
When are cystic ovaries associated with infertility?
Polycystic - more than 10
Where do tumours in the ovary most commonly arise from?
Epithelial components or germ cells
What is the suspensory ligament?
Attachment of the ovary to the posterior uterine wall
What is the ovarian ligament?
Attachment of the ovary to the uterus
What is the round ligament?
Attachement of the uterus to the labia majora, passing through the inguinal canal
What is the broad ligament?
Base of the peritoneum
What is the uterosacral ligament?
Attachment of the uterus posteriorly to the sacral spine
What is the cardinal ligament?
Attachment of the uterus to the lateral abdominal wall
What is the pubouterine ligament?
Attachment of the uterus to the pubic symphysis
What is the function of the mesovarium?
Attaches the ovary to the posterior of the broad ligament
Which ligament passes from the ovary to the uterus posteroinferior to the uterotubal junction?
Ovarian ligament
Why does the ovarian artery originate from the renal level of the aorta?
Embryonic origin is at this level
What is the venous drainage of the ovaries?
R ovarian -> IVC
L ovarian -> L renal vein -> IVC
(same as testicular venous drainage in male)
What is the lymphatic drainage of the ovaries?
drains to para-aortic nodes
How does the surface appearance of a pre-pubertal ovary compare to that of a post-pubertal ovary?
Pre-pubertal surface is smooth, post-pubertal surface epithelium becomes progressively scarred and distorted because of repeated rupture of ovarian follicles and discharge of oocytes during ovulation
What is the function of the uterine tubes?
Transfer and transport of the ovum from the ovary to the uterus
What are the sections of the uterine tube?
Funnel shaped abdominal opening - ostium with fingerlike projections called fimbria
Infundibulum
Ampulla
Isthmus (narrowest part) opens into the uterine cavity
Describe the lumen of the oviducts.
Mucous membrane is thrown into complex folds thus the lumen in cross section appears as a labyrinthine system of narrow spaces
Describe the epithelia of the fallopian tubes.
Simple columnar with ciliated and non-ciliated (secretory) cells
What is the function of the fimbria and cilia?
Movement of the fimbria over the surface of the ovary and ciliated cells are thought to assist in the transfer of the ovum from the surface of the ovary into the uterine tube and cilia throughout move the ova along the tube
What is the function of the secretory cells in the fallopian tube?
Provide nutrients to the early conceptus following fertilisation
What are the layers of the fallopian tube?
Mucous membrane
Muscular layer
Serous coat
What is the function of the muscular layer of the fallopian tube?
Contractions of the smooth muscle layer assists with the transport of sperm to the site of fertilisation and the transport of the conceptus to the uterus
What is salpingitis?
Inflammation of the uterine tube caused by microorganisms.
What are the complications of salpingitis?
Infertility due to fusions or adhesions of the mucosa and thus partial or complete block of the lumen
May also result in ectopic pregnancy