embryology - urinary and repro system development

Question 1

what forms the kidneys, ureter and gonads

Answer 1

intermediate mesoderm

Question 2

what di the kidney and ureter develop from

Answer 2

urogenital ridge

Question 3

how does the urogenital ridge form the kidney and ureter

Answer 3

differentiates into gonadal ridge

gives rise to gonad and nephrogenic cord laterally - this forms the kidney and ureter

Question 4

where does the kidney develop

Answer 4

pelvis

ascends to abdomen by week 12

Question 5

what does the cloaca give rise to

Answer 5

urogenital sinus which develops bladder and urethra and some parts of male/female reproductive tract

Question 6

what is the nephrogenic cord

Answer 6

part of the urogenital ridge

Question 7

what are the three stages of development of the nephrogenic cord

Answer 7

pronephros
mesonephros
metanephros - final kidney

Question 8

where does the metanephros drain

Answer 8

nephritic duct then cloaca

Question 9

what is the cloaca

Answer 9

caudal end of enfolded yolk sac

Question 10

what is the cloacal membrane formed by

Answer 10

ectoderm and endoderm

Question 11

what is the urorectal septum and what does it do

Answer 11

septum that divides cloaca into the urogenital sinus and anal canal

Question 12

what does the urogenital sinus form

Answer 12

bladder and urethra

Question 13

where do primordial germ cells originate

Answer 13

endoderm lining of yolk sac in hind gut at 6 weeks gestation
migrate to gonads

Question 14

what forms the primitive sex cords

Answer 14

epithelium of gonadal ridge

Question 15

what is the indifferent gonad

Answer 15

develops in gonadal ridge
made of a combination of germ cells and primitive sex cord cells
can develop into testes or ovaries

Question 16

what are primitive sex cords

Answer 16

elongated projections that form from the gonadal ridge

Question 17

how do ovaries develop

Answer 17

primitive sex cords extend into medulla then degenerate

seondary sex/cortical cords develop and surround ovaries to form primordial follicles

Question 18

when is the ovarian reserve established

Answer 18

20 weeks gestation

Question 19

what is the function of the SRY gene

Answer 19

produces SRY protein (testes determining factor) which promotes testes formation

Question 20

how are the testes formed

Answer 20

primitive sex cords extend into medulla and form testis cords then seminiferous tubules and rete testes

Question 21

how are sertoli cells formed

Answer 21

AMH causes them to be derived from surface epithelium

Question 22

how are leydig cells formed and when do they produce testosterone

Answer 22

from intermediate mesoderm

produce testosterone from 8 weeks

Question 23

where to the gonads originate

Answer 23

posterior abdominal wall

Question 24

when do the testes reach the inguinal ring

Answer 24

by 7 months

Question 25

what is cryptorchidism

Answer 25

undescended testicle

Question 26

what is cryptorchidism

Answer 26

undescended testicle

Question 27

what are the two sets of genital ducts

Answer 27

mesonephric duct - next to indifferent gonad | paramesonephric duct - lateral to mesonephric duct

Question 28

what does AMH do

Answer 28

causes paramesonephric ducts to regress | mesonephric ducts from male repro organs

Question 29

what is the trigone formed from in males and females

Answer 29

mesonephric ducts

Question 30

how does the mesonephric duct persist in males | what does it form

Answer 30

AMH testosterone epididymis, vas deferens, seminal vesicles

Question 31

what does the mesonephric duct form in males

Answer 31

epididymis vas deferens seminal vesicles

Question 32

what happens to the mesonephric duct in females

Answer 32

regresses

Question 33

what can the remnants of the mesonephric duct in females form

Answer 33

epoophoron paraphoron (small cystic structures) gartners duct cyst

Question 34

what do the paramesonephric ducts form in females

Answer 34

fuses and canalises to form uterus and upper 2/3 of vagina | unfused portions form fallopian tubes

Question 35

what forms the lower 1/3 of the vagina

Answer 35

urogenital sinus

Question 36

what forms the hymen

Answer 36

fusion of the paramesonephric ducts and urogenital sinus

Question 37

where to urogenital folds form

Answer 37

either side of cloacal membrane

Question 38

how is the genital tubercle formed

Answer 38

fusion of urogenital folds

Question 39

what happens to the genital tubercle in males

Answer 39

elongates to form penis

Question 40

wat happens to genital tubercle in females

Answer 40

forms labia minora and clitoris

Question 41

what happens to the labioscrotal swelling and urogenital folds in males

Answer 41

labioscrotal swelling folds fuse posteriorly | urogenital folds fuse posteriorly to form penile urethra

Question 42

what happens to the labioscrotal folds in females

Answer 42

form labia majora