Urinary embryology

Question 1

from what part of the mesoderm does the urogenital system come from

Answer 1

the intermediate plate mesoderm

Question 2

what peritoneal position does the intermediate plate mesoderm take

Answer 2

retropeitoneal

Question 3

what is allantois

Answer 3

an outpouching of endoderm at the handgun that extends into the body stalk

Question 4

what is the cloaca

Answer 4

posterior opening for digestive, urinary and reproductive tracts

Question 5

how does the cloaca divide

Answer 5

anteriorly forms the urogenital sinus

divides to form the rectum (GI tract)

Question 6

what drains into the urogenital sinus

Answer 6

mesonephric duct

Question 7

what does the urogenital sinus go on to form

Answer 7

the urinary bladder, caudal end forms the urethra

Question 8

how many sets o kidneys develop sequentially during nephrogenesis

Answer 8

3

Question 9

what happens to the intermediate mesoderm in the NECK region in week 4

Answer 9

becomes the pronephros

Question 10

what is the pronephros

Answer 10

the pronephric duct + rudimentary pronephric tubules

Question 11

where does the pronephric duct drain to

Answer 11

the cloaca

Question 12

what happens to the pronephros in week 5

Answer 12

all degenerates EXCEPT the pronephric duct

Question 13

what happens to the intermediate mesoderm in the TRUNK region in week 4

Answer 13

becomes the mesonephros

Question 14

what happens to the pronephric duct

Answer 14

becomes the mesonephric duct

Question 15

what drains into the mesonephric duct

Answer 15

mesonephric tubules

Question 16

what is the function of the mesonephros

Answer 16

functions as the kidneys for approx. 4 weeks

Question 17

what are the metanephros

Answer 17

definitive kidneys

Question 18

when do the metanephros start to develop

Answer 18

week 5

Question 19

when do the metanephros start to function

Answer 19

week 9

Question 20

how do the metanephros develop

Answer 20

a ureteric bud develops off the mesonephric duct

Question 21

what happens to the mesonephos

Answer 21

incorporated into the developing gonad

Undifferentiated cells from the yolk sac migrate in to form the spermatogonia/ oogonia

Question 22

in males what happens to the mesonephric tubules and duct

Answer 22

tubules - become the rate testis

duct - becomes the vas deferens

Question 23

in females what happens to the mesonephric tubules and duct

Answer 23

degenerate

Mesonephros incorporated into the ovary though

Question 24

what is the further development of the ureteric bud

Answer 24

• repeated branching at distal end
• stalk becomes ureter
• expanded cranial end becomes renal pelvis

Question 25

what forms the major calyces

Answer 25

the first 4 generations of distal branches of the ureteric bud

Question 26

what forms the minor calyces

Answer 26

the second 4 generations of distal branches of the ureteric bud

Question 27

what forms the collecting tubules

Answer 27

the remaining generations of branches of the ureteric bud

Question 28

what do the ureteric bud and metanephric mesioderm do to each other

Answer 28

reciprocally induce each other

Question 29

what comprises the nephron

Answer 29

Renal corpuscle + PCT + Loop of Henle + DCT

Question 30

what comprises the uriniferous tubule

Answer 30

nephron + collecting duct

Question 31

what develops from the metanephric mesoderm

Answer 31

the nephron

Question 32

what 4 things develops from the ureteric bud

Answer 32

collecting duct, calyces, pelvis and ureter

Question 33

where do kidneys initially lie

Answer 33

either side of the bladder in the developing pelvis

Question 34

why do the kidneys appear to "ascend" during development

Answer 34

lower body differentially grows inferiorly away from them

Question 35

where do kidneys come to lie finally

Answer 35

upper abdomen - T12-L3

Question 36

how does the hilum of the kidney rotate

Answer 36

about 90 degrees ventral to medial

Question 37

when does "ascent" of the kidneys stop

Answer 37

when they come into contact with the adrenal gland

Question 38

what happens to kidney vascular supply during ascent

Answer 38

segmental breakdown and reform

Question 39

summary - what does the allantois and cloaca develop into

Answer 39

the Urinary bladder and urethra

Question 40

summary - what does the intermediate mesoderm develop into

Answer 40

rudimentary pronephros in neck (week 4), Mesonephros in trunk region (week 5 to 9) with a duct and tubules. Duct drains into cloaca

Question 41

summary - where does the ureteric bud develop from

Answer 41

caudal end of the mesonephric duct

Question 42

summary - what do the ureteric bud branches form

Answer 42

form the renal pelvis, calyces and collecting duct

Question 43

summary - what is the relationship between the ureteric bud and metanephric mesoderm

Answer 43

reciprocally induce each other

Question 44

summary - why do the kidneys appear to "ascend"

Answer 44

due to differential growth of abdominopelvic structures - also acquire new blood vessels

Question 45

summary - what happens to the hilum of the kidneys

Answer 45

rotate to face medially