repro embryology

Question 1

where do primordial germ cells migrate to

Answer 1

gonadal ridge

Question 2

what 3 types of cells are found in gonadal ridge

Answer 2

primordial germ cells
mesothelial cells
mesenchymal cells

Question 3

what do primordial cells give

Answer 3

future gametes
male = spermatogonia
female = oogonia

Question 4

what do mesothelial cells do

Answer 4

structures which will harbour and help in development of primordial germ cells

Question 5

what structures are mesothelial cells in M&F

Answer 5

male = seminiferous tubules
female = follicles

Question 6

what are mesenchymal cells

Answer 6

supporting cells
male = Leydig cells
female = stroma

Question 7

which layer is genital tract developed from

Answer 7

intermediate mesoderm

Question 8

what are the 2 genital ducts

Answer 8

mesonephric - Wolffian (male)
paramesonephric - Mullerian (female)

give internal reproductive structures

Question 9

what structures does mesonephric (wolffian) duct give

Answer 9

epididymis
vas deferens
seminal vesicle

Question 10

what structures does paramesonephric (Mullerian) duct give

Answer 10

uterus
fallopian tube
cervix
upper 1/3 vagina

Question 11

dihydrotestosterone function

Answer 11

provides prostate, penis and scrotum
external genitalia

Question 12

what does sertoli cells produce

Answer 12

MIF

Question 13

gubernaculum becomes what?

Answer 13

ovarian ligament and round ligament of ovary

Question 14

what week do germ cells begin to migrate from endoderm lining of yolk sac to genital ridges

Answer 14

4th week

Question 15

what week do the germ cells reach the genital ridges

Answer 15

6th week

Question 16

what forms indifferent gonad

Answer 16

germ cells and primitive sex cords

Question 17

how do primitive sex cords form

Answer 17

epithelium of genital ridges proliferates and penetrates the intermediate mesoderm

Question 18

what gene does Y chromosome contain

Answer 18

SRY

Question 19

what does SRY gene do

Answer 19

stimulate development of primitive sex cords to form testis (medullary) cords

Question 20

a portion of testis cords breaks off to form what

Answer 20

future rete testis

Question 21

remaining testis cords contain 2 types of cells

Answer 21

sertoli
germ

Question 22

Leydig cells are derived from?

Answer 22

intermediate mesoderm

Question 23

what do Leydig begin in week 8

Answer 23

production of testosterone - which drives differentiation of internal and external genitalia

Question 24

role of appendix testis and location

Answer 24

no physiological function
small portion of tissue located on upper pole of each testicle

Question 25

how does appendix testis form

Answer 25

paramesonephric duct

Question 26

in the presence of which hormone does paramesonephric duct degenerate

Answer 26

anti-Mullerian

Question 27

where is anti-Mullerian hormone produced

Answer 27

sertoli cells in the testes

Question 28

in females, what does the degeneration of mesonephric duct leave behind

Answer 28

vestigial remnant: Gartner's duct

Question 29

absence of anti-Mullerian hormone allows for development of what duct

Answer 29

paramesonephric duct

Question 30

3 parts of paramesonephric duct

Answer 30

cranial horizontal caudal

Question 31

cranial paramesonephric duct becomes?

Answer 31

fallopian tubes

Question 32

horizontal paramesonephric duct becomes?

Answer 32

fallopian tubes

Question 33

caudal paramesonephric duct becomes?

Answer 33

fuses to form the uterus, cervix, and upper 1/3 vagina

Question 34

how does lower 2/3 vagina form

Answer 34

sinovaginal bulbs

Question 35

where are sinovaginal bulbs derived from

Answer 35

from pelvic part of urogenital sinus

Question 36

which week does external genitalia development begin

Answer 36

3rd week

Question 37

how are cloacal folds formed

Answer 37

mesenchymal cells from primitive streak migrate to cloacal membrane to form pair of cloacal folds

Question 38

cranially, what do folds do?

Answer 38

fuse to form genital tubercle

Question 39

caudally, what do folds do?

Answer 39

divide into urethral folds (anterior) anal folds (posterior)

Question 40

what develops either side of urethral folds

Answer 40

genital swellings

Question 41

rapid elongation of genital tubercle causes what to form

Answer 41

becomes the phallus

Question 42

urethral folds are pulled to form what

Answer 42

urethral groove

Question 43

folds close over by when and form what

Answer 43

by 4th month and form the penile urethra

Question 44

genital swellings become what

Answer 44

scrotal swellings

Question 45

scrotal swellings move where to form what

Answer 45

move caudally to form scrotum

Question 46

oestrogens are responsible for ?

Answer 46

external genitalia development

Question 47

genital tubercle elongates to form what

Answer 47

clitoris

Question 48

urethral folds and genital swellings do not fuse, but instead form what

Answer 48

labia minora and labia majora respectively

Question 49

urogenital groove remains open, forming what?

Answer 49

vestibule into which urethra and vagina open

Question 50

gubernaculum

Answer 50

ligamentous structure formed from mesenchyme

Question 51

around week 28 what happens with testes

Answer 51

pass through inguinal canal

Question 52

testes reach scrotum at what week

Answer 52

week 33

Question 53

testes blood supply

Answer 53

testicular arteries

Question 54

where do testicular arteries branch from

Answer 54

lumbar aorta

Question 55

adult remnant of gubernaculum in males

Answer 55

scrotal ligament