Lecture 45: Urogenital Development

Question 1

urogenital system derives from what kind of mesoderm

Answer 1

intermediate mesoderm

Question 2

3 primitive kidneys

Answer 2

pronephros
mesonephros
metanephros

Question 3

which kidney primordia becomes the permanent kidney

Answer 3

metanephros

Question 4

ureter derivative

Answer 4

mesonephric duct

Question 5

what structure forms nephrons

Answer 5

metanephric blastema

Question 6

bladder and pelvic urethra derived from

Answer 6

urogenital sinus

Question 7

2 regions of urogenital sinus

Answer 7

cranial
caudal

Question 8

cranial region of primitive urogenital sinus generates what structure

Answer 8

bladder

Question 9

caudal region of primitive urogenital sinus generates what structures

Answer 9

pelvic urethra
prostate and bulbourethral glands in males

Question 10

origin of pelvic urethra

Answer 10

urogenital sinus

Question 11

initial indifferent stage of gonadal development

Answer 11

epiblast –> primordial germ cells
cells move to yolk sac and end up along dorsal mesentery of hindgut

Question 12

what stimulates differentiation into testis

Answer 12

SRY gene of Y chromosome

Question 13

what stimulates differentiation into ovaries

Answer 13

absence of SRY gene of Y chromosome

Question 14

mesonephric ducts give rise to what structures (3): hint males

Answer 14

epididymis
ductus deferens
ampullary and vesicular glands

Question 15

paramesonephric duct gives rise to what structures (3): hint female

Answer 15

uterine tubes
uterus
cranial region of vagina

Question 16

caudal region of vagina and vestibule derived from

Answer 16

urogenital sinus

Question 17

what do androgens stimulate in males

Answer 17

genital tubercle gives rise to erectile tissue and tunica albuginea of penis

Question 18

what do estrogens stimulate in females

Answer 18

genital tubercle gives rise to clitoris

Question 19

testis descent is necessary for what process

Answer 19

spermatogenesis

Question 20

2 phases of testis descent

Answer 20

intra abdominal
extra abdominal

Question 21

what is testis descent caused by (what structure)

Answer 21

gubernaculum

Question 22

intra abdominal phase of testis descent

Answer 22

reduced size/length of gubernaculum

Question 23

extra abdominal phase of testis descent

Answer 23

depends on androgens
gubernaculum increases in size/thickness but also reduces in length

Question 24

during extra abdominal phase of testis descent, what does reduced length of gubernaculum do

Answer 24

pulls testis through canal and take a scrotal position

Question 25

genital ridge gives rise to

Answer 25

testis or ovaries

Question 26

what happens to mesonephric duct in females

Answer 26

degenerates in response to no androgens

Question 27

paramesonephric ducts give rise to

Answer 27

female genital ducts

Question 28

what happens to paramesonephric ducts in males

Answer 28

degenerates in response to mullerian inhibiting substance