Renal Embryo

Question 1

Where is the urogenital ridge and from what embryonic cell layer is it derived?

Answer 1

raised area on either side of the dorsal aorta

intermediate mesoderm

Question 2

During what time is the mesonephros functional?

Answer 2

week 6-10

Question 3

In what week does the pronephros form? When does it degenerate?

Answer 3

Early week 4

degenerates by 24-25 days (3-4 days later)

Question 4

What part of the pronephros persists & contributes to mesonephros

Answer 4

pronephric ducts

Question 5

What is the function of fetal kidneys

Answer 5

PRODUCE AMNIOTIC FLUID - fetal kidneys do not filter blood b/c placenta does that

Question 6

From what structure do glomeruli/renal corpuscles originate?

Answer 6

intermediate mesoderm => mesonephric tubules => primitive glomeruli

Question 7

From what structure does the vas deferens derive?

Answer 7

mesonephric tubules

Question 8

When and where does the metanephros first arise?

Answer 8

during the 5th week, caudal to mesonephros

Question 9

When is there a functional and definitive kidney?

Answer 9

by the 9th-10th week

Question 10

What is the origin of the ureteric bud?

Answer 10

outgrowth of mesonephric duct

Question 11

What is the origin of the metanephric blastema

Answer 11

nephrogenic cord

Question 12

from what structure does the collecting system of of the urinary tract originate?

Answer 12

ureteric bud

Question 13

what induces formation of metanephric vesicles and what do they become?

Answer 13

the arched collecting tubule induces metanephric blastema cells to form metanephric vesicles, which elongate to become metanephric tubules

Question 14

What do the metanephric tubules become?

Answer 14

proximal and distal convoluted tubules & loop of henle

Question 15

4 structures arising from ureteric bud

Answer 15

ureter
renal pelvic
major and minor calyces
collecting ducts

Question 16

4 structures arising from metanephric blastema

Answer 16

Bowman’s capsule
proximal convoluted tubule
loop of henle
distal convoluted tubule

Question 17

what structure prevents the ascent of a horseshoe kidney

Answer 17

inferior mesenteric artery

Question 18

what divides the GI and urinary systems from one another in the fetus

Answer 18

urorectal septum

Question 19

what are the three parts of the urogenital sinus and what to they become

Answer 19

vesical part => bladder
pelvic part => neck of bladder, membranous & prostatic urethra
phallic part => spongy urethra / vaginal lining

Question 20

From what structure does the trigone of the bladder originate?

Answer 20

mesonephric and ureteric ducts

intermediate mesoderm

Question 21

embryonic origin of the bladder’s transitional epithelium

Answer 21

endoderm (urogenital sinus)

Question 22

embryonic origin of the bladder’s submucosa & muscularis

Answer 22

splanchnic mesoderm

Question 23

From what cell layer do chromaffin cells originate?

Answer 23

neural crest

Question 24

what do fetal cortical cells do?

Answer 24

fetal cortex secretes DHEA which is converted to estradiol in the placenta
essential for maintaining pregnancy

Question 25

From what cell layer does the urogenital sinus arise?

Answer 25

hindgut endoderm