Female - Anatomy & Physiology Flashcards
Mesovarium
- double folds of peritoneum
- attaches ovaries to the broad ligament
- carries the blood supply, lymphatic drainage & nerve supply of the ovary.
Broad ligament
- peritoneum
- drapes over the uterus
Ovarian ligament
connects the ovary to the uterus
Suspensory ligament
connects the ovary to the pelvic wall
Function of the ovaries (2)
- steroid production
- gametogenesis (production of gametes/germ cells)
Ovary - blood supply
Principally from the ovarian arteries which arise from the aorta, just below the renal arteries.
The ovary is approx. ______cm long, _____cm wide & ____cm thick & weighs about _____g.
4cm, 3cm, 2cm, 10g.
The ovary is divided into the:
- Outer cortex
- Inner medulla
Granulosa cells produce…
(ovary cortex)
estradiol
Differentiated theca cells produce…
(ovary cortex)
androgens
Outer cortex of the ovary
- covered by tunica albuginea (connective tissue capsule) & a layer of simple epithelium = consisting of ovarian surface epithelial cells (repairs the wall of the ovary after ovulation).
- composed of dense cellular stroma containing ovarian follicles = where each one contains a primary oocyte surrounded by follicle cells.
Inner medulla of the ovary
Neurovascular elements innervate the medulla
The stroma cells outside the granulosa cell layer differentiate into:
- Theca interna = more vascular & secretes androstenedione (which is converted later on by granulosa cells to estrogen)
- Theca externa = more fibrous, smooth muscle. Gradually merges with the stroma.
Ovarian follicles
Fluid-filled structures that each contain an oocyte.
Polar body
- Byproduct of an oocyte meiotic division
- contains haploid number (23) of c/somes
Physiology of the Ovary
A) Shortly before ovulation, meiosis is completed in the primary oocyte in response to the luteinizing hormone (LH) surge.
B) The oocyte casts off the 1st polar body resulting in the # of c/somes in the remaining nucleus being reduced from 46 to 23.
(primary oocyte & the 1st polar body each contain haploid # (23) of c/somes)
- at this stage the ripe follicle is about 20mm in diameter.
C) At ovulation it ruptures, releasing the oocyte usually into the fimbriated end of the fallopian tube.
The follicle in the ovary collapses
- granulosa cells become…
- theca interna forms…
- The granulosa cells become luteal cells
while the - Theca interna forms the theca lutein cells
Explain the Corpus luteum
- development, appearance, secretion, degeneration.
- develops & projects from the surface of the ovary.
- can be recognized by the naked eye by its crinkled outline & yellow appearance
- its cells secrete estrogen & progesterone
- it degenerates in about 10 days if the ovum isn’t fertilized. Then a small amount of bleeding occurs into its cavity, the cells undergo hyaline degeneration & a corpus albicans is formed.
- if pregnancy does occur, the corpus luteum grows & may reach 3cm in diameter, & persists for 80-120 days & then gradually degenerates.
Oviducts / Uterine ducts / Fallopian Tubes are muscular tubes with:
- distal ends close to the surface of each ovary
- proximal ends traversing the wall of the uterus
Oviducts / Uterine Tubes / Fallopian Tubes are divided into 4 regions:
(from the ovary to the uterus)
- Infundibulum with fimbriae
- Ampullae
- Isthmus
- Intramural / Interstitial portion
3 functions of the Oviducts / Uterine Tubes / Fallopian Tubes
- Captures the cumulus-oocyte complex & transfers it to the ampullary-isthmic junction where fertilization takes place.
- Provides a site for sperm storage,
- sperms remain viable by adhering to epithelial cells lining the isthmus. - Secretes fluids that provide nutritional support to the preimplantation embryo.
3 walls/layers of the Oviducts / Uterine Tubes / Fallopian Tubes
- Endosalpinx
- Myosalpinx
- Perisalpinx
Endosalpinx wall/layer
- mucosa
- lined by simple epithelium thrown into folds & made up of 2 cell types:
1) Ciliated epithelium = propels the cumulus-oocyte complex towards the uterus.
2) Secretory cells = produces protein-rich mucous that maintains healthy epithelium.
Myosalpinx wall/layer
- muscularis (2 layers) = smooth muscular layer
Perisalpinx wall/layer
- outer lying connective tissue
Uterus
- a hollow, muscle-walled organ in the pelvis communicating with each fallopian tube, & through its cervix, the vagina.
Pre-pregnancy - uterus weight
40g
Full term pregnancy - uterus weight
1000g or 1kg
Relations of the uterus
- Peritoneum
- the body & fundus are covered with the peritoneum.
- over the rest of the uterus, the attachment is dense & it can’t be stripped off the uterine muscle.
Relations of the uterus
- Anterior
- Uterovescial pouch
- Bladder
Relations of the uterus
- Lateral
Broad ligaments with their contents
Relations of the uterus
- Posterior
- Pouch of Douglas / Recto-uterine pouch
- Rectum
4 regions of the Uterus
- Fundus
- Body
- Isthmus
- Cervix
Cervix consists of 3 parts:
- Cervical canal
- Internal os
- External os
Uterus wall - 3 concentric layers
- Endometrium
- Myometrium
- Perimetrium
Perimetrium
- outer layer / serosa
- is continuous with the broad ligament
Myometrium
- thick, middle layer
- is formed from 3 intertwining layers of smooth muscle =
- non-pregnant uterus = muscle cells are less than 0.25mm in length.
- pregnancy = smooth muscle cells increase both in size & in number.
Structures in the Internal genitalia
- vagina
- uterus = fundus, body, cervix, isthmus
- ovaries
Uterus - blood supply
- from the uterine & ovarian arteries (mostly)
Uterine artery
- a branch of the internal iliac artery
- runs in the lower edge of the broad ligament to the junction of the uterine body & cervix, before running up the side of the uterus giving off several branches into the myometrium.
- the ureter lies immediately beneath the uterine artery.
What does the saying ‘water under the bridge’ mean in terms of anatomy?
It means the ureter is under the uterine artery.
The Uterus is supported by ligaments.
- What are the principal ligaments that support the uterus? (3)
- transverse cervical / cardinal ligaments
- uterosacral ligaments
- round ligament
Round ligament
- rises from the fundus of the uterus, anterior to the fallopian tube & passes into the inguinal canal ending in the labia majora.
Broad ligament
2 folds/layers of peritoneum that runs over the fallopian tubes
- anteriorly to the uterovesical reflection
- posteriorly to the rectovaginal reflection
Transverse cervical / Cardinal / Mackenrodt ligaments
attaches the lateral side of the vagina & cervix (of the uterus) to the lateral side of the pelvic wall.
Uterosacral ligament
Attaches the cervix (of the uterus) to the sacrum.
In pregnancy, the ligaments are…
- stretched
- thickened
- soften = because of the progesterone & relaxin effect on collagen.
Cervix (of the uterus)
- barrel-shaped canal at the bottom of the uterus.
- mostly connective tissue with muscle at upper & lower end (internal & external os).
- in late pregnancy, the ground substance of connective tissue becomes softer with a greater water content & the cervix becomes softer clinically.
Vagina
a fibromuscular canal that extends from the vestibule of the vulva to the cervix, around which it is attached to form the fornices.
4 functions of the Vagina
- Passageway for menstrual flow
- Receives sperm & semen from the male
- Female organ of copulation (sexual intercourse)
- Birth canal during delivery of the infant
Anterior vaginal wall
6-9 cm long
Posterior vaginal wall
10-12 cm
Vaginal wall
- childbirth
- normal
- in childbirth = capable of great distension after the prolonged hormonal stimulation of pregnancy.
- normally = the walls are normally flattened in the anteroposterior diameter giving the appearance of the letter ‘H’ in a cross-section.
The Vaginal walls have:
1) Outer connective tissue layer = to which ligaments are attached. It also contains blood vessels, lymphatics & nerves.
2) Muscular layer = consists of an: (variable thickness & function)
- outer longitudinal layer
- inner circular layer
3) Epithelium of stratified squamous epithelium = in adult women contains glycogen.
- Composed of 3 layers:
1. Basal layer
2. Functional layer
3. Cornified layer
Vagina
- Epithelium of stratified squamous epithelium
Epithelium of stratified squamous epithelium = in adult women contains glycogen.
- Composed of 3 layers:
1. Basal layer
2. Functional layer
3. Cornified layer
- Undergoes cyclical changes during the menstrual cycle & characteristic changes during pregnancy.
- After menopause, it atrophies so that smears taken from postmenopausal women contain a high proportion of basal cells.
Vaginal fluid
- composed of cervical secretion & transudation through the vaginal epithelium.
- allows colonization of lactobacilli which produce lactic acid from the glycogen in the epithelial cells.
Vulva / External genitalia of the female includes:
(9)
- mons pubis
- labia majora
- labia minora
- clitoris
- vestibule
- external urethra
- meatus
- Bartholin
- Hymen
Mons pubis
- pad of fat that lies over the pubic symphysis
- covered with skin in which hair grows profusely from puberty to menopause.
Labia major
- 2 folds of skin that enclose the vaginal opening.
- made up of fatty tissue that is very sensitive to estrogen stimulation.
- the skin is of the labia major is covered with hair after puberty
Clitoris
- contains erectile tissue & is attached to the pubic arch by its crura.
- folds of skin running forward from the labia minor form the prepuce of the clitoris.
Labia minor
- delicate folds of skin, containing fibrous tissue & numerous blood vessels & erectile tissue.
- skin contains sebaceous glands
Vestibule
- part of the vulva between the labia minora; into which opens the vagina, with the external meatus of the urethra in front & the ducts of the Bartholin glands behind.
External urethral meatus
- opening of the urethra covered with squamous epithelium.
- Skene’s ducts from the posterior urethral glands open on to the posterior margin of the meatus.
External urethral meatus
- opening of the urethra covered with squamous epithelium.
- Skene’s ducts from the posterior urethral glands open onto the posterior margin of the meatus.
Bartholin glands
- a pair of glands, the ducts of which are lined by columnar epithelium.
- resembles salivary glands
- secretion is colorless & mucoid = produced mainly on sexual excitement.
Hymen
- circular or crescentic fold of squamous epithelium & connective tissue which partly closes the vaginal entrance in young women.
- shape & size varies
- is often ruptured or stretched by tampon insertion or by intercourse - childbirth destroys it.
Perineum = is a diamond-shaped area between the thighs that is circumscribed:
- anteriorly
- laterally
- posteriorly
Anteriorly = pubic symphysis
Laterally = ischial tuberosities
Posteriorly = coccyx
Perineum - 2 distinct triangle bases, which are formed by…
an imaginary horizontal line extending between the ischial tuberosities of the ossa coxae.
2 distinct triangles bases
- Anterior / Urogenital Triangle
- Posterior / Anal Triangle
Anterior / Urogenital Triangle
- contains the urethral & vaginal orifices
Posterior / Anal triangle
- location of the anus
