Embryology

Question 1

What is the embryological origin for the kidney?

Answer 1

mesoderm

Question 2

What develops from the intermediate mesoderm?

Answer 2

nephrotome

Question 3

What happens to the intermediate mesoderm at the cranial end?

Answer 3

begins to segment to form the pronephros

Question 4

What are the pronephros?

Answer 4

a vistigial structure- is only temprorary

Question 5

What develops alongside the pronephros?

Answer 5

the mesonephric duct

Question 6

What happens later to the intermediate mesoderm more caudally?

Answer 6

segments to form the mesonephros

Question 7

What is the mesonephros?

Answer 7

temprorary kidney between weeks 6-10 then regress once the kidney proper has developed

Question 8

How do the mesonephros develop?

Answer 8

take on a nephron shape, connect to mesonephric duct

Question 9

What does the kidney develop from?

Answer 9

metanephros (NOT mesonephros) the ureteric bud and metanephric blastema

Question 10

What do the ureteric buds sprout from?

Answer 10

the distal mesonephric ducts

Question 11

What is the metanephric blastema?

Answer 11

sacral portion of the intermediate mesoderm

Question 12

How do the ureteric buds and metanephric blastema come to form the kidney?

Answer 12

ureteric bud sprouts to penetrate the metanephric blastema

Question 13

What does the ureteric bud form?

Answer 13

the collecting system

Question 14

What is the collecting system made up of?

Answer 14

ureter; renal pelvis; major calyces; minor calyces and collecting ducts

Question 15

How does the ureteric bud grow into the metanephric blastema?

Answer 15

brances to separate the blastema- develop gross lobes

Question 16

What happens after the ureteric bud has branched into the metanephric blastema?

Answer 16

insussuseption and then branches and then more intussusception

Question 17

What is the purpose of the intussusception?

Answer 17

proximal branches coalesce again to create larger spaces to collect urine in

Question 18

What does hte metanephric blastema form?

Answer 18

the nephrons

Question 19

How does the metanephric blastema form the nephrons?

Answer 19

there is a small “cap” of blastema tissue at the end of the bud branches which form a vesicle which then fuses with the collcting system

Question 20

Where do the kidneys develop in the embryo?

Answer 20

pelvis near the bifurcation of the aorta

Question 21

What does the cloaca develop from?

Answer 21

hindgut endoderm

Question 22

What does the cloaca form?

Answer 22

the rectum and the primitive urogenital sinus

Question 23

What does the primitive urogenital sinus give rise to?

Answer 23

the bladder; pelvis urethra and the definitive urogential sinus

Question 24

What is the allantois?

Answer 24

an opening from the cloaca into the umbilical cord

Question 25

What originally connects with the bladder instead of the ureteric bud?

Answer 25

mesonephric duct- they need to switch

Question 26

What does the mesopnephric duct form in the males?

Answer 26

vas deferens

Question 27

What does the mesonephric duct form on its descent to switch places with the ureteric bud?

Answer 27

the smooth trigone