UG Development 2 Flashcards
Describe the significance of pronephros, mesonephros, and metanephros on kidney development, and how development of the permanent kidney accounts for clinical conditions such as horseshoe kidney, pelvic kidney, and multiple renal arteries.
1
Q
From cranial to caudal, what does the nephrogenic cord form?
A
- pronephros
- mesonephros
- metanephros
2
Q
What is the first functioning kidney?
A
mesonephros
3
Q
What is the mesonephric duct (wolffian duct) and what does it do?
A
- a duct of the UG ridge
- connects mesonephric tubules in the nephrogenic cord with the hindgut cloaca
- Functions as the emryonic ureter
4
Q
Where do the permanent kidneys develop from and how does this happen?
A
- originates from ureteric bud
- comes off the mesonephric duct
- invades metanephric mass of intermediate mesoderm (nephrogenic cord)
5
Q
What is the later developmental process (8 weeks onwards) of the following?
Kidneys?
Bladder?
Allantois?
Mesonephros?
A
- Kidneys - ascend over time
-
Bladder - develops from UG sinus (also forms urethra and related glands)
- above the entrance of the mesonephric and paramesonephric ducts
- Allantois - degenerates to form the urachus
- Mesonephros - degenerates as a urinary structure (tubules and ductules)
6
Q
What leads to multiple renal arteries?
A
As the kidney ascends, sequential arteries hook up to it, and these may persist.
7
Q
What leads to horseshoe kidney? What are some related pathologies?
A
- fusion of the ureteric buds that hook around the inferior mesenteric artery as they ascend
- multiple buds can lead to multiple kidneys/ureters
- buds can also fail to ascend
8
Q
What leads to a pelvic kidney?
A
failure of the kidneys to ascend
