Development of the Urinary System

Question 1

The urinary system is derived from which layer of the trilaminar disc?

Answer 1

Intermediate mesoderm (in particular the urogenital ridge)

Question 2

What are the three developing systems to form the kidneys?

Answer 2

Pronephros
Mesonephros
Metanephros

Question 3

Describe the development of the pronephros

Answer 3

First system to develop
Consists of pronephric duct which descends down to the cloaca
Recedes, has no functional purpose

Question 4

Describe the development of the mesonephros

Answer 4

Takes over from the pronephros
Now called mesonephric duct (a.k.a Wolffian)
Sprouts mesonephric tubules which form Bowman’s capsules
Sprouts the ureteric bud
The ureteric bud makes contact with the intermediate mesoderm to form the metanephric blastema

Question 5

Describe the development of the metanephros

Answer 5

Takes over from the mesonephros to form definitive kidney

Question 6

Which structures are derived from the ureteric bud?

Answer 6

Ureter, renal pelvis, collecting ducts

Question 7

Which structures are derived from the metanephric blastema?

Answer 7

Nephrons