Development of the Urinary System Flashcards
Functionally the urogenital system can be divided into two entirely different components which are what?
The urinary system and the genital system
The urogenital system’s two parts develop from what?
A common mesodermal ridge (intermediate mesoderm)
What is the urogenital ridge?
This is intermediate mesoderm that bulges into the intraemrbyonic coelmic cavity
The urogenital ridge differentiates into what two things?
The nephrogenic cord/ridge and the genital ridge
Through lateral folding where does the nephrogenic cord end up?
Retroperitoneal
What are the three developmental kidney systems?
Pronephros, mesonephros, and metanephros
When does the pronephros appear?
Early in week 4
Is the pronephros ever functional?
No
Where does the mesonephros appear?
In thoracic and lumbar segments of intermediate mesoderm
In the mesonephros urine is produced and drains along what?
Mesonephric (wolffian) duct to cloaca/bladder
What does the mesonephros initiate?
The ureteric bud/metanephric diverticulum growth
What structure marks the beginning of the metenephros?
When the ureteric bud (metenephric diverticulum) sprouts from the distal end of the mesonephric duct
What is the metanephric blastema?
A structure that forms the glomeruli and tubules of the nephrons
What are the two components of the metanephros?
Collecting portion (ureteric bud) and excretory portion (metanephric blastema)
If what is missing or abnormal a kidney will not form?
A bud
What is reciprocal induction?
Close proximity to ureteric bud will induce nephron differentiation
What are the collecting portion structures of the metanephros?
Ureter, renal pelvis, and major and minor calyces
What are the excretory portion structures of the metanephros?
Bowman’s capsule, proximal convoluted tubule, loop of henle, distal convoluted tubule
Cloaca in the hindgut becomes divided by what? (ventral and dorsal)
Urorectal septum, ventral urogenital sinus and dorsal anorectal canal
What is the trigone of the bladder?
The distal portions of the mesonephric ducts and the attached ureteric ducts, become incorporated into the posterior aspects of the bladder
In females the development of urethra comes from what?
The whole urethra and part of the vagina arise from the pelvic part of the urogenital sinus
In males the urethra comes from what?
Prostatic and membranous parts of the urethra arise from the pelvic part of the urogenital sinus while the spongy urethra comes from the phallic part.
