Embryo- Genital development

Question 1

what embryonic layer gives rise to the genital system?

Answer 1

Intermediate mesoderm

Question 2

what layer of the mesoderm becomes retroperitoneal?

Answer 2

Intermediate mesoderm

Question 3

what does the intermediate mesoderm form?

Answer 3

Bilateral urogenital ridges

Question 4

what are the 2 urogenital ridges?

Answer 4

Nephrogenic cord

Gonadal ridge

Question 5

which portion of the urogenital ridge is lateral?

Answer 5

Nephrogenic cord

Question 6

which portion of the urogenital ridge is medial?

Answer 6

Gonadal ridge

Question 7

during what week do we see sex differentiation?

Answer 7

Week 7

Question 8

When is the “indifferent stage”?

Answer 8

Weeks 1-6

Question 9

what type of cells migrate to gonadal ridges?

Answer 9

Primordial germ cells

Question 10

What happens in week 5?

Answer 10

Intermediate mesoderm thickens to form gonadal ridge

Question 11

Mesothelial cord cells form solid….

Answer 11

form solid gonadal cords that sink into underlying mesenchyme

Question 12

what is SRY?

Answer 12

“sex determining region of the Y chromosome”

Question 13

What is TDF?

Answer 13

Testes-determining factor

Question 14

what are Leydig cells?

Answer 14

Leydig cells (stromal CT cells) -develop from mesenchyme of gonadal ridge.

-Produce: TESTOSTERONE

Question 15

What are Sertoli cells?

Answer 15

• “caretakers” of primordial germ cells

- develop from gonadal cord cells

Question 16

What do the sertoli cells form?

Answer 16

1) Seminiferous tubules

2) Rete testes

Question 17

which cell type surrounds the primordial germ cells?

Answer 17

Leydig cells (interstitial cells)

Question 18

which cells develop in close proximity to the PGCs? (primordial germ cells)

Answer 18

Sertoli cells

Question 19

what signals male genital development?

Answer 19

Testosterone

which cells produce this?

Question 20

what does the mesonephric duct form

Answer 20

ductus deferens
Epididymis

(mesonephric tubules form efferent tubules)

Question 21

Superior end of mesonephric duct forms what?

Answer 21

Epididymis

Question 22

Mesonephric tubules form what?

Answer 22

efferent ductules

Question 23

what induces mesonephric duct to form male genital ducts?

Answer 23

Testosterone

Question 24

Caudal ends of mesonephric ducts develop into what?

Answer 24

1) seminal vesicles

2) Ejaculatory ducts

Question 25

what are ALL the structures that are developed from the Mesonephric ducts?

Answer 25

- Epididymis - Ductus deferens - Seminal Vesicle - Ejaculatory duct

Question 26

the gonadal cords form what in males?

Answer 26

- Seminiferous tubules | - Retes testes

Question 27

MIH (Mullerian Ducts regress) is produced by what?

Answer 27

Sertoli cells

Question 28

what does MIH cause?

Answer 28

causes the mullerian ducts to degrade/regress

Question 29

what is the remnant of the Mullerian duct in men?

Answer 29

the Appendix testes

Question 30

the prostate and bulbouretheral glands are endodermal outgrowths from what

Answer 30

Urogenital sinus

Question 31

where does the gubernaculum extend?

Answer 31

from the gonad to the labioscrotal swelling (future scrotal sac)

Question 32

what is the shortening of the gubernaculum responsible for?

Answer 32

pulls the testis, ductus deferens, and testicular vessels downward through the abdominal wall

Question 33

name the 3 layers of the scrotum

Answer 33

- Internal spermatic fascia - Cremasteric muscle - External spermatic fascia

Question 34

what layer of the scrotum is formed from the external oblique aponeurosis?

Answer 34

External spermatic fascia

Question 35

Congenital inguinal hernia-

Answer 35

Patent processus vaginalis

Question 36

what leads to development of fluid-filled cysts in the scrotum?

Answer 36

Hydrocoele

Question 37

What is cryptorchidism?

Answer 37

failure of the testes do descend

Question 38

which 2 genetic factors are females lacking?

Answer 38

- No SRY | - No TDF

Question 39

what do stromal cells of the ovary develop from?

Answer 39

Mesenchyme of gonadal ridge

Question 40

what are follicular cells? | what do they develop from?

Answer 40

“caretakers” of PGCs develop from gonadal cord cells

Question 41

what cell type surrounds the PGCs also form ovarian follicles

Answer 41

Follicular cells

Question 42

what does a lack of testosterone cause?

Answer 42

Mesonephric duct regression

Question 43

What does a lack of MIH lead to

Answer 43

continued growth & development of mullein ducts

Question 44

whats another name for mullein ducts?

Answer 44

paramesophrenic ducts

Question 45

The Müllerian ducts will form what?

Answer 45

The Müllerian ducts will form the uterine tubes, uterus, and superior vagina

Question 46

what is formed by The cranial ends of the Müllerian ducts?

Answer 46

uterine tubes

Question 47

what is formed by the uterovaginal primordium?

Answer 47

forms uterus and superior vagina

Question 48

what fuses to give the uterovaginal primordium?

Answer 48

caudal ends of mullein ducts

Question 49

The uterovaginal primordium comes into contact with the dorsal wall of the urogenital sinus and forms what?

Answer 49

Sinovaginal bulb

Question 50

what is the vaginal plate?

Answer 50

Sinovaginal bulbs separating from the urogenital sinuses -fuse with uterovaginal primordium

Question 51

what forms the inferior vagina?

Answer 51

urogenital sinus (NOT mullerian ducts)

Question 52

The greater vestibular glands, urethral glands, and paraurethral glands are all from what structure?

Answer 52

urogenital sinus

Question 53

Labioscrotal swellings in females

Answer 53

- Fuse posteriorly and anteriorly | - Unfused portions become labia majora

Question 54

Urethral folds in females

Answer 54

remain unfused as labia minora

Question 55

Urethral folds in males

Answer 55

Fold under ventrally + fuse to form penile shaft

Question 56

Labioscrotal swellings in men

Answer 56

Fuse at midline to form the scrotum