Urinary System Embryology

Question 1

What are the 3 structures the mesoderm splits off to form?

Answer 1

Paraxial mesoderm
Intermediate plate mesoderm
Lateral plate mesoderm

Question 2

Which embyological structure forms the urogenital system?

Answer 2

Intermediate plate mesoderm

Question 3

Which embryological structure forms the somites?

Answer 3

Paraxial mesoderm

Question 4

The lateral plate mesoderm forms what?

Answer 4

Body cavity and coverings

Question 5

Lateral folding of the embryo cause the lateral plate mesoderm to form what?

Answer 5

Somatic mesoderm
Splanchnic mesoderm
(intra-embryonic coelom)

Question 6

What is the allantois?

Answer 6

Outpouching of endoderm at the hindgut

Question 7

The embryonic cloaca is made of the formation of which structures?

Answer 7

Hindgut

Allantois

Question 8

The hindgut and allantois are divided by which structure?

Answer 8

Urorectal septum

Question 9

The cloaca divides to form what?

Answer 9

Rectum

Urogenital sinus

Question 10

The mesonephric duct drains into what?

Answer 10

The urogenital sinus

Question 11

The urogenital sinus goes on to form what?

Answer 11

Urinary bladder

Caudal end → urethra

Question 12

Week 4, intermediate mesoderm in the neck region of the embryo forms what?

Answer 12

The pronephros

Question 13

What is the pronephros?

Answer 13

Pronephric duct + rudimentary pronephric tubules

Question 14

The pronephric duct drains into what?

Answer 14

The Cloaca

Question 15

At what week of embryonic development does the pronephros degenerate?

Answer 15

Week 5 (except pronephric duct)

Question 16

The pronephric duct goes on to form what? What week/

Answer 16

Mesonephric duct (week 4)

Question 17

What drains into the mesonephric duct?

Answer 17

Mesonephric tubules

Question 18

How long does the mesonephros function as the kidney?

Answer 18

4 weeks

Question 19

When does the metanephros develop? When does it begin to function?

Answer 19

Develops - Week 5

Functions - Week 9

Question 20

The metanephros consists of what?

Answer 20

Ureteric bud

Metanephric mesoderm

Question 21

What happens to the mesonephros?

Answer 21

Incorporated into the developing gonad

Question 22

What is the fate of the mesonephric tubules?

Answer 22

Become rete testis

Degenerate in women

Question 23

What is the fate of the mesonephric duct?

Answer 23

Becomes vas deferens in male

Degenerates in women

Question 24

What happens to the ureteric bud?

Answer 24

Repeated branching at the distal end

Question 25

The ureteric stalk becomes what in an adult?

Answer 25

Ureter

Question 26

The first 4 generations of branches of the ureteric bud form what?

Answer 26

The major calyces

Question 27

The second 4 generations of branches of the ureteric bud form what?

Answer 27

Minor calyces

Question 28

After the first 8 generations of branches, what do subsequent generations form?

Answer 28

Collecting tubules

Question 29

How do the ureteric bud and metanephric mesoderm stimulate eachother?

Answer 29

Reciprocal induction

Question 30

What structures make up the uriniferous tubule?

Answer 30

Nephron and Collecting duct

Question 31

What structures make up the nephron?

Answer 31

Renal corpuscle
Proximal collecting tubule
Loop of Henle
Distal collecting tubule

Question 32

What structures develop from the metanephric mesoderm?

Answer 32

Nephron

Question 33

What structures develop from the ureteric bud?

Answer 33

Collecting duct
Calyces
Pelvis
Ureters

Question 34

Why do the kidneys appear to ascend?

Answer 34

The lower body grows ‘away’ from the kidneys

Question 35

At what vertebral levels do the kidneys lie?

Answer 35

T12-L3

Question 36

How does the position of the hilum change?

Answer 36

Rotates 90deg

Ventral to medial facing

Question 37

When does ascend of the kidneys stop?

Answer 37

When the kidneys contact the adrenal glands