Embryology of the Reproductive System Flashcards
what process has to occur for the definitive endoderm and mesoderm to form?
invagination of the epiblast cells through the primitive streak
describe the 3 main groups of the mesoderm?
paraxial
intermediate
lateral plate
the ____ section of the embryo undergoes cranial folding
sagittal
the __ section of the embryo undergoes lateral folding
axial
the urogenital system arises from what layer?
INTERMEDIATE mesoderm
what is the cloaca?
posterior orifice that serves as the only opening for the digestive, reproductive, and urinary tracts
what cells within the yolk sac migrates to the intermediate mesoderm?
primordial germ cells
what forms genital ridges?
coelomic epithelium
what structure forms somatic support cells for somatic support cells around primordial germ cells?
proliferating epithelium
embryological form of wolffian ducts?
mesonephric
embryological form of mullerian ducts?
paramesonephric
the genital ducts connect to the ___ wall of the ____ sinus
posterior
urogenital
sexual differentiation occurs from week _ onwards
7
male development is triggered by the presence of…
SRY (Sex determining region of Y) transcription factor
what do somatic support cells eventually form in males?
sertoli cells
what connects the mesonephric tubules to the testis cords
rete testis
what degenerates the paramesonephric duct in males and how?
sertoli cells secrete anti-mullerian hormone (AMH)
what stimulates the production of leydig cells?
sertoli cells acting upon gonadal ridge cells
testosterone induces formation of..
epididymis
vas deferens
seminal vesicles
dihydrotestosterone induces formation of…
induces male specific ext genitalia development and prostate
presentation of persistent mullerian duct syndrome
uterus, vagina and uterine tubes with male ext genitalia
testes in ovarian location
what vertebral level do testes originate at
T10
what structure pulls testes caudally?
gubernaculum
what is cryptorchidism?
failure of 1 or more testis to descend
name the 3 male accessory glands
prostate
bulbourethral gland
seminal vesicle
what triggers female development?
the ABSENCE of SRY transcription factor
somatic support cells differentiate into what in females?
granulosa cells
what do granulosa cells do?
surround primary oocyte to form primordial follicles in the ovary
what cells stimulate oestrogen and external genitalia formation?
thecal cells (basically female leydig cells)
mullerian/paramesonephric ducts give rise to…
uterine tubes
uterus
SUPERIOR vagina
what portion of the mullerian duct opens up into the coelomic cavity?
cranial
what portion of the mullerian duct crosses the mesonephric duct?
horizontal
describe the relationship between the caudal portion of the mullerian duct and the mullerian duct on the other side?
they fuse
what is the uterovaginal canal? what does it form?
fused caudal portion of both mullerian ducts
forms uterus and superior vagina
what part of the male external genitalia is not formed by the intermediate mesoderm?
foreskin (ectoderm)
external urethral orifice
what is hypospadias?
external urethral orifice lies in an abnormal position on the ventral aspect of the penis
what structure eventually differentiates to become the clitoris?
genital tubercle
