UG Development 2

Question 1

From cranial to caudal, what does the nephrogenic cord form?

Answer 1

• pronephros
• mesonephros
• metanephros

Question 2

What is the first functioning kidney?

Answer 2

mesonephros

Question 3

What is the mesonephric duct (wolffian duct) and what does it do?

Answer 3

• a duct of the UG ridge
• connects mesonephric tubules in the nephrogenic cord with the hindgut cloaca
• Functions as the emryonic ureter

Question 4

Where do the permanent kidneys develop from and how does this happen?

Answer 4

• originates from ureteric bud
• comes off the mesonephric duct
• invades metanephric mass of intermediate mesoderm (nephrogenic cord)

Question 5

What is the later developmental process (8 weeks onwards) of the following?

Kidneys?

Bladder?

Allantois?

Mesonephros?

Answer 5

• 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)

Question 6

What leads to multiple renal arteries?

Answer 6

As the kidney ascends, sequential arteries hook up to it, and these may persist.

Question 7

What leads to horseshoe kidney? What are some related pathologies?

Answer 7

• 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

Question 8

What leads to a pelvic kidney?

Answer 8

failure of the kidneys to ascend