Repro Flashcards
What is the embryonic origin of the urogenital ridge
intermediate mesoderm region
What does urogenital ridge give rise to?
Embryonic kidney
Gonad
What drives the male gonad development?
SRY gene on short (p) arm of Y chromosome
What happens to the gonad under the Y chromosome influence?
Primodal germ cells colonise the medulla
-> testis and thick tunica albuginea develop
What happens to the gonad without the Y chromosome influence
Primodal germ cells colonise the cortex
-> medullary cords degenerate and ovaries develop
What makes up the mesonephric/Wolffian duct ?
Urogenital sinus and anus divided by uroqrectal septum
What happens to the mesonephric/wolffian ducts under the influence of testosterone?
mesonephric duct sprouts ureteric buds
they make separate openings
->prostate and prostatic urethra forms
What happens to the mesonephric/ wolffian ducts without the influence of testosterone?
mesonephric duct sprouts ureteric buds
ureteric bud expands and mesonephtic duct regresses
Embryonic origin of the uterus and cervix?
Paramesonephric duct
AKA Mullerian duct
What prevents the uterus from forming in males?
Mullerian Inhibiting Substance
secreted by sertoli cells
What influences the development of the external genitalia?
Dihydrotestosterone -> male
What attaches the testis to the inguinal region?
gubernaculum
What prevents the ovary descend past the pelvic brim
paramesonephric ducts
Male gametes formation
Mitosis:
spermatogonia (before birth) -> raw material
-> A1 spermatogonia
-> primary spermatocytes (linked by cytoplasm)
Meiosis:
spermatogenesis -> spermatids (remodelled to..)
-> spermatozoa
Semen contains secretions of (4):
seminal vesicle (60% of vol)
prostate (20%)
bulbs-urethral glands
+ sperm
Female gametes formation
Oognia (primordiale germ cells in gonadal cortex) mitosis by mid-gestation.
- > primary oocyte (meiosis arrested at prophase 1)
- > primordial follicle (oocyte surrounded by granulose cells layer)
- > ovum
Ovum production
small number of primordial follicles begin to develop further at the beginning of the cycle -> 1/2 complete the the development
- > pre-antral ovum (indeed. of hormones)
- > antral ovum (LH and FSH cause…)
- > pre-ovulatory follicle
Pre-ovulatory follicle structure
theca (externa and int)
granulose cells
Antrum
primary oocyte