Reproductive System Development - Severson Flashcards
What area of mesoderm in the developing embryo gives rise to the urogenital system?
Intermediate Mesoderm
What areas of structures give rise to the urinary system and genital system?
Nephrogenic ridge gives rise to the URINARY system.
Gonadal/Genital ridge gives rise to the GENITAL system.
What is the difference between genetic sex and phenotypic or genital sex?
Genetic Sex: is determined at the time of fertilization
Phenotypic/Genital Sex: does not manifest until the seventh week of development
What hormone is responsible for establishing phenotypic maleness?
Testosterone
What gene is responsible for the development of the testes?
SRY gene (Sex-determining Region of Y)
-responsible for the production of testis-determining factor that induces the formation of testes
What developmental defect underlies the most common abnormality of sexual differentiation?
Klinefelter Syndrome (47, XXY)
What chromosome is lacking in Turner Syndrome?
lack of paternal sex chromosome (45, XO)
What type of tissue (testes or ovaries) would be found in the gonads of a true hermaphrodite?
Possess BOTH testicular and ovarian tissue (ovotestis)
***Extremely rare condition.
What is the source of the gametes (primordial germ cells) that migrate into the genital ridge?
Umbilical vesicle (yolk sac)
What tissues constitute the early genital ridge or gonads?
Mesothelium (coelomic epithelium) + underlying mesenchyme + primordial germ cells
The primordial germ cells in the male and female migrate into what developmental structures?
Genital (gonadal) ridge
Where are Sertoli Cells located?
Cortical cords (which later become seminiferous tubules)
What adult male structures are formed from the cortical cords?
Seminiferous tubules
Tubuli recti (straight tubules)
Rete testis
What embryologic structure forms the Efferent Ductules?
Mesonephric ductules (tubules)
What hormone stimulates the interstitial cells of Leydig to produce the androgenic hormones?
Human chorionic gonadotropin (hCG)
What hormone is produced by the Leydig cells?
Testosterone and androstenedione
What hormone stimulates the Sertoli cells?
hCG
What hormone is produced by the Sertoli cells and what effect does it have on the developing embryo?
anti-mullerian hormone => suppresses development of the paramesonephric (Mullerian) ducts
What cells give rise to the oogonia?
primordial germ cells
How are the primordial germ cells multiplied in the genital ridge?
mitosis
Why do the oogonia undergo meiosis?
they are under the influence of meiosis-stimulating factor