ILA10 - Reproductive Flashcards
What is the reproductive tracts derived from embryologically?
Intermediate mesoderm
How long are the gonads indifferent?
Until 6 weeks
When is the sex of the fetus determined?
At fertilization
What determines the sex of the fetus?
SRY gene on Y chromosome, which produces testis determining factor
What are the two ducts for reproductive development?
Mesonephric (Wolffian, male) and paramesonephric (Mullerian, female)
Describe the development of the male reproductive tract.
1) Sex determining region Y (SRY) on Y chromosome present
2) SRY protein coded for (transcription factor) causes testis determining factor to be produced
3a) Testis produce testosterone (Leydig cells) causing Wolffian duct to develop
3b) Testis also produce Mullerian inhibiting factor, causing Mullerian duct regression
4) Testosterone of also converted, by 5 alpha reductase, to dihydrotestosterone, which causes development of external genitalia
Describe the development of the female reproductive tract.
1) No Y chromosome so no SRY
2) No gonadal hormone influence
3) Female genitalia develop by default from genital ridges
4) Lack of testosterone= Wolffian regresses
5) Lack of MIF = Mullerian grows
6) Lack of dihydrotestosterone = female external genetalia
Name some of the ligaments supporting the female reproductive organs.
Round, suspensory, broad, cardinal
What does the urogenital sinus form in males?
Penis, foreskin and scrotum. Utethra and bladder
What does the urogenital sinus form in females?
Bladder, urethra, lower 1/3 vagina, paraurethal glands, greater vestibular glands
What does the round ligament support?
Attaches the uterus to the mons pubis and labia majora, travels via the inguinal canal
Maintains antiflexion of the uterus
What does the suspensory ligament support?
Connects ovary to pelvis wall. Contains ovarian artery and vein
What does the broad ligament support?
- It is a continuation of the peritoneum
- Connects the side of the uterus to the lateral pelvis
- Contains uterine tubes, ovary, ovarian artery and vein, uterine artery and vein, ovarian and round ligament
- Forms mesovarium
What does the cardinal ligaments connect?
Cervix to lateral pelvic wall
Contains uterine artery and vein
What do the internal and external os divide?
- Internal divides uterus and cervix
- External divides cervix and vagina
Describe the length of the fallopian tube (ovary to uterus).
Fibrae, infudibulum, ampulla, isthmus then intramural
Describe the blood supply of the female genitalia.
- Ovarian artery (straight from the abdominal artery)
- Uterine, vaginal and internal pudendal arteries from the internal iliac artery
What is the nerve supply of the female genitalia?
- Sympathetic is hypogastic plexus
- Parasympathetic is pelvic splachnic nerve
What is the ovaries covered by?
Modified mesothelium
Describe the stroma of the ovaries.
- Cortex is composed of spindle stromal cells and ovarian follicles
- Medulla is composed of loose fibroelastic tissue with blood vessels, lymphatics and nerves
Describe the stages of maturation for a follicle
1) Primordial follicles -lie in periphary of cortex
-simple squamous layer, granulosa cell coat
2) Primary follicles -due to FSH cell proliferate and zona pellucida forms
3) Secondary follicle -antrum forms, theca interna and externa form, all supported by cumulus oophorus
4) Graafian- thick zona pellucida, layer of granulosa cells=corona radiata (not the one in the brain)
Follicle leaves
5) Corpus luteum -if pregnancy occurs it will enlarge
6) Corpus albicans -produces progesterone
What cell types are in the fallopian tubes?
- secretory (uterine end)
- ciliated (infundibular end)
What does the uterus contain?
Endometrium and myometrium
What are the two coverings in the cervix?
1) Endocervix -simple columnar ciliated with crypts
2) Ectocervix -dense smooth muscle stroma, non-keratinising strat. squamous
These for the transformation zone, separation varies in life
What are the layers in the vagina?
- Mucosa (non-keratinising strat. squamous)
- Muscle (smooth, inner circular, outer longitudinal)
- Adventitia (loose connective tissue)
Where is gonadotropin-releasing hormone (GnRH) released from?
Hypothalamus
What does GnRH stimulate?
LH and FSH release from anterior pituitary