Human Embryology 6 - Development of the Urogenital System Flashcards
Urogenital ridge is divided into
- Mesonephric ridge - outside part giving rise to urinary system
- Gonadal ridge - inner side giving rise to the genital system
Permanent kidney rises from
Metanephros
Degenerate kidneys present during embryonic development
- Pronephros
- Mesonephros
- Metanephros
Prenephros duct degenerates by the end of the _______ week
Fourth
Mesonephros consists of two structures which open laterally into the mesonephric duct
- Glomeruli
- Mesonephric tubule
Metanephros have two origins
- Ureteric bud
- Metanephrogenic tissue
Definition: Ureteric bud
Formed from the outgrowth of the Mesonephric duct near the cloaca and develops into the ureter (stem), renal pelvis, major and minor calyces and collecting tubules (branches)
Metanephrogenic tissue
Formed from the caudal portion of the intermediate mass of mesonephric ridge, surrounds the end of the ureteric bud and gives rise to the nephrons
Development of nephrons
- Metanephric vesicles formed in Metanephrogenic tissue which elongate to form S-shaped tubules
- Capillaries grow into and form glomeruli
- Renal capsule and renal tubule connect with arched collecting tubules
Function of the permanent kidneys begin at
3rd month
Definition: Cloaca
Just superior to the cloaca membrane, the primitive gut forms an expansion
The _______ is formed by the division of the cloaca
Urogenital sinus
Divisions of the Urogenital sinus
- Cranial portion - bladder proper
- Pelvic part - prostatic urethra and parts of vagina in female
- Caudal portion - penile urethra in males and vestibule in females
Failure in connection between the nephron and the collecting system
Polycystic kidney
During ascent, failure to pass through arterial fork and remaining in the pelvis
Ectopic kidney (pelvic kidney)
