Embryonic Development

Question 1

what are the 3 duct systems in the development of the kidney

Answer 1

paranephros, mesonephros, metanephros

Question 2

where does the paranephros develop from

Answer 2

the cervical region of intermediate mesoderm

Question 3

which duct system starts to produce urine

Answer 3

mesonephros

Question 4

true or false: the mesonephros can store water/urine

Answer 4

false - it can only produce it

Question 5

what is the ureteric bud

Answer 5

a sprouting from the mesonephros which interacts with intermediate mesoderm to produce the metanephros

Question 6

what does the ureteric bud develop into

Answer 6

the ureter

Question 7

what happens to the mesonephric duct once the metanephros is produce

Answer 7

it either regresses or is used in the development of the male reproductive tract

Question 8

how is the urogenital sinus created

Answer 8

by dividing the cloaca with the urorectal septum

Question 9

what is the urachus

Answer 9

part of the urogenital sinus which is continuous with the umbilicus

Question 10

what does the urogenital sinus develop into

Answer 10

the urethra and bladder

Question 11

what are the 4 parts of the urethra in males

Answer 11

Pelvic:

• pre-prostatic
• prostatic
• membranous

Phallic:
- spongy

Question 12

how do the kidneys migrate

Answer 12

they ascend cranially, mostly due to the elongation of the embryo but also due to movement of the kidney itself

Question 13

how are the accessory vessels produced

Answer 13

as the kidneys ascend they create new blood vessels with the old ones regressing. if the old vessels don’t regress properly them remain as accessory vessels

Question 14

what type of blood vessels are accessory vessels

Answer 14

end arteries

Question 15

what is renal agenesis

Answer 15

where there is failure of interaction between the ureteric bud and the intermediate mesoderm causing lack of development of the kidney

Question 16

what happens to the amniotic fluid in renal agenesis

Answer 16

if there is no development of either kidney then the amniotic level will fall

Question 17

what is pelvic kidney

Answer 17

where a kidney remains in the pelvic region

Question 18

what are the causes of pelvic kidney

Answer 18

poor development, defects in tissue, genetic abnormalities

Question 19

what is horseshoe kidney

Answer 19

where during the ascent of the kidneys, they are blocked by abdominal aortic vessels and so the bottoms of the kidneys fuse together to give 1 horseshoe shaped kidney

Question 20

what is the duplication defect

Answer 20

where there is partial or complete splitting of the ureteric bud

Question 21

what would happen if their is an ectopic ureteral opening inferior to the bladder

Answer 21

there would be urinary incontinence as the urethra doesn’t have sphincters to hold the urine in

Question 22

what is hypospadias

Answer 22

where there is incomplete fusion of the genital folds to form the spongy urethra

Question 23

when is a urorectal fistula formed

Answer 23

when the urorectal septum doesn’t divide the cloaca properly to burst through the membrane

Question 24

when might urine leak out of the umbilicus following birth

Answer 24

when the urachus doesn’t close up properly

Question 25

what does the urachus form after birth

Answer 25

it closes to form the median umbilicus ligament

Question 26

what is the urachus

Answer 26

part of the urogenital sinus which is continuous with the umbilicus