Development of the Urinary System Flashcards
What embryonic layer derives the Urinary System?
Intermediate Mesoderm - between paraxial mesoderm and splanchnic mesoderm
Development of the Pronephros
Marker that sets up the rest of kidney development
Bilaterally develop on day 23
Consists of solid intermediate mesoderm rod connected to epithelium lined buds
Rudimentary - degenerates within a few days
Mesonephros
Functions as primitive kidney with primitive nephrons
Develop in weeks 4-10, funcitonal at week 6
What does the Mesonephros consist of
Mesonephric vesicles
Mesonephric Tubules
Mesonephric Ducts
What arises from the Mesonephric Vesicles
Bowman’s capsule
What arises from the Mesonephric Tubules
Tubular part of nephron
What arises from the Mesonephric Ducts?
Collecting duct
How does the Mesonephric duct develop?
Grows caudally toward cloaca
Hollows caudal to cranial upon contact with cloaca
Diverticulum develops
Metanephros
Becomes the permanent kidney
What are the components of the Metanephros
Uteric bud
Metanephrogenic blastema
Uteric bud arises….
Collecting portions of the kidney - ureter, pelvis, calyces, collecting tubules
Metanphrogenic blastema arises….
Excretory portion of kidney - Bowman’s capsule, convoluted tubules, loop of Henle
What portions of the mesonephric ducts persists in male genitalia?
Duct = ductus deferens Tubule = efferent ductules of testes
What is the original blood supply before the ascension of the kidneys?
Common Iliac artery
What is the terminal blood supply of the kidneys?
Renal arteries off of the abdominal aorta
What structure can block the ascension of the kidneys?
Common iliac artery - can lead to ectopic kidney
What is a Horseshoe kidney?
When the Inferior Mesenteric artery blocks ascent and the inferior poles fuse
What role does the urorectal septum play in urinary system development
Divides the cloaca into the urogenital sinus and anorectal canal
What are the derivates of the urogenital sinus in females?
Urinary bladder
Urethra
Vestibule of vagina
Vestibular glands
What are the derivatives of the urogenital sinus in males?
Urinary bladder
Urethra
Prostate
Bulbourethral glands
What happens to the allantois
Closes off the urachus
What does the obliterated urachus become?
Median umbilical ligament - under the medial umbilical fold
What are some abnormalities that can come from the urachus?
Urachal cyst
Urachal sinus
Urachal fistula
Exstrophy of the urinary bladder
The anterior abdominal wall fails to close
