UG System

Question 1

When do you get anomalies in UG development?

Answer 1

when things don’t fuse together or where buds don’t come off

Question 2

stages of developing kidney

Answer 2

pronephros -> mesonephros -> metanephros

Question 3

origin of kidneys?

Answer 3

two sources of mesoderm:

• metanephric bud grows out and induces metanephrogenic tissue/metanephrogenic blastoma (mesoderm) to form part of kidney
• metanephric bud/ureteric bud forms drainage part of kidney and ureter

Question 4

fate of mesonephric duct system in both sexes

Answer 4

female: degrades -> epoophoron
male: becomes part of male genital system (vas deferens)

Question 5

paramesonephric ducts in both sexes

Answer 5

female: become genital system
male: have anti-mullerian factor that prevents these ducts from forming

Question 6

another name for paramesonephric ducts

Answer 6

mullerian ducts

Question 7

function of pronephric kidney

Answer 7

don’t really function, but have nephrogenic cords that eventually drain into the cloaca

Question 8

where does the urethra come from?

Answer 8

cloaca -> UG sinus proper

Question 9

what forms the water under the bridge relationship?

Answer 9

septum growing out of cloaca to form two entries + as testes descend, cross over the ureter

Question 10

origin of tubule system in glomerulus

Answer 10

mesonephric duct

Question 11

what parts of kidney are derived from ureteric bud?

Answer 11

collecting ducts into calyxes and into ureter (drainage part)

Question 12

what parts of kidney are derived from mesonephrogenic parts?

Answer 12

PCT, DCT

Question 13

turning of the kidneys

Answer 13

start facing anteriorly, then turn medially so that the hilum sits on the psoas

Question 14

origins of vagina

Answer 14

proximal part: paramesonephric system

distal part: vaginal plate

Question 15

blood supply of vagina

Answer 15

proximal: internal iliac
distal: internal pudendal

Question 16

origin of adrenal glands

Answer 16

mesenchymal condensations in abdomen

Question 17

what forms the trigone of the bladder?

Answer 17

exstrophy of the mesonephric ducts into the bladder wall (UG sinus envelops ureters into the wall)

Question 18

origins of bladder?

Answer 18

wall of trigone: mesonephric duct system

rest of bladder: UG sinus from cloaca

Question 19

urachal anamolies

Answer 19

• urachal cyst
• urachal sinus
• urachal fistula

Question 20

what happens if the body wall doesn’t zip together to enclose the pelvic cavity?

Answer 20

exstrophy of the bladder - gives you bilateral parts of external genitalia and body wall

Question 21

origin of parts of penis

Answer 21

spongy urethra: from distal part of UG sinus (endoderm)

external urethral orifice + navicular fossa: ectoderm that grows up against the endoderm

Question 22

origin of prepuce/foreskin?

Answer 22

ectoderm

Question 23

phimosis

Answer 23

prepuce fuses to glans

Question 24

development of medulla of adrenal glands?

Answer 24

neural crest cells invade developing cortex and form adrenal chromaphin cells

Question 25

development of gonadal ridge?

Answer 25

embryonic germ cells from yolk sac migrate into gonadal ridge -> differentiation of ridge -> sex cords grow inwards and subdivide different structures

Question 26

development of testes?

Answer 26

testis determining factor -> seminiferous cords eventually connect into mesonephric duct > sperm go through epididymis into vas deferens

Question 27

what is derived from gonadal ridge?

Answer 27

ovaries and testes

Question 28

development of ovaries?

Answer 28

cortical cords from gonadal ridge grow in and become surface epithelium of developing ovary

Question 29

another name for mesonephric ducts

Answer 29

wolffian ducts

Question 30

Gartner’s cyst

Answer 30

remnant of mesonephric duct

Question 31

Mullerian tubercle

Answer 31

= sinus tubercle -> paramesonephric ducts induce this part of UG sinus to form the vaginal plate

Question 32

origin of ducts in males: of prostate, ejaculatory duct, vas deferens?

Answer 32

prostate: from urethra from UG sinus from cloaca (endoderm)

ejaculatory duct and vas deferens: from mesonephric duct (mesoderm)

Question 33

what does the labioscrotal fold become?

Answer 33

(body wall) -> labia and scrotum

Question 34

what does the genital tubercle become?

Answer 34

glans and clit