3: Embryology Flashcards
What germ layer do the kidneys originate from?
Mesoderm
Which particular part of the mesoderm do the kidneys develop from?
Intermediate mesoderm
What structure do the kidneys originate from?
Pronephros
The pronephros develops into which structure?
Mesonephros
How does the pronephros descend into its correct position for development?
Mesonephric duct
What does the mesonephros develop into, forming the permanent kidney?
Metanephros
Which embryological structures do the metanephros develop from?
Ureteric bud
Metanephric blastema
What duct does the ureteric bud come from?
Mesonephric duct
What is the other origin of the kidneys apart from the ureteric bud?
Which germ layer does it come from?
Metanephric blastema
Intermediate mesoderm in the sacrum
The ___ ___ pushes into the ___ ___.
(ureteric bud, metanephric blastema)
ureteric bud pushes into the metanephric blastema
What happens when the ureteric bud fails to push into the metanephric blastema?
Kidney agenesis
Lack of a kidney
What structures of the kidney does the ureteric bud develop into?
Collecting system
so the collecting ducts all the way to the ureters
What embryological origin of the kidney forms the nephrons themselves?
Metanephric blastema
What embryological structures form the
a) collecting system
b) nephrons
of the kidney?
a) Ureteric bud
b) Metanephric blastema
Which body cavity do the kidneys originate in?
What do they need to do after that?
Pelvic cavity
Ascend to the retroperitoneal space of the abdomen
After they’ve ascended, are the kidneys intraperitoneal or retroperitoneal?
retroperitoneal
As the kidneys ascend from the pelvis to the abdomen, which blood vessel do they draw a supply from?
Abdominal aorta
As the kidneys rise, the vessels they draw blood from degenerate. What happens when this doesn’t occur?
Accessory renal arteries
What can happen if one or both kidneys fail to ascend?
Pelvic kidney
Remains in the pelvis
What is a horseshoe kidney?
Metanephrons (pre-kidneys) FUSE at inferior poles, make a weird horseshoe shape and are more inferior than normal
What is the cloaca?
Early hindgut with ONE opening for the GI, renal and reproductive tracts
What germ layer does the cloaca originate from?
Endoderm
In which space do the bladder, urethra and rectum develop?
Primitive urogenital sinus
What is the difference between the primitive and definitive urogenital sinuses?
Primitive urogenital sinus forms earlier and has openings for GI, renal and repro tracts
Definitive urogenitial sinus separates from anorectal canal and has urethra and bladder only
What does the definitive urogenital sinus develop into?
Urethra and bladder
How do the mesonephric ducts factor in to the development of the bladder?
Form the posterior wall, which becomes the trigone
What structure, found superior to the bladder, exits in the umbilical cord to drain the bladder of the fetus?
Allantois
What does the allantois develop into in adults?
Urachus
closed off space
Problems with the ___ can cause bladder defects in newborns.
urachus
