i hate embryos

Question 1

what is the indifferent stage of development

Answer 1

for the first 6-7 weeks, males and females are phenotypically indistinguishable.

Question 2

what is gonadal tissue derived from

Answer 2

mesoderm adjacent to the mesonephros

Question 3

describe migration of germ cells

Answer 3

they migrate from the yolk sac along the allantois, followed by dorsal mesentary into genital ridges adjacent to mesonephric region

Question 4

what are genital ridges

Answer 4

area encompassing coelomic epithelium and primitive sex cords

Question 5

what is absolutely essential for gonad development

Answer 5

germ cells

Question 6

what can happen with abnormal germ cell migration

Answer 6

teratomas

Question 7

what does SRY gene encode for

Answer 7

testis determining factor (TDF)

Question 8

describe functions of TDF

Answer 8

stimulates differentiation into testes and forming of primary sex cords, promoting formation of leydig cells and sertoli cells

Question 9

what happens without TDF

Answer 9

male structures do not differentiate, leading to development of ovaries and secondary sex cords

Question 10

primitive sex cords develop from…

Answer 10

coelomic epithelium

Question 11

what do primitive sex cords form in males

Answer 11

rete testis and seminiforous tubules

Question 12

where are primitive sex cords located

Answer 12

in the medulla

Question 13

what is testosterone needed for in terms of developing structures

Answer 13

epididymis, vas deferens, seminal vesicles

Question 14

what is DHT

Answer 14

hormone made from testosterone via 5a-reductase

Question 15

what is DHT important for developing

Answer 15

penis, scrotum, prostate

Question 16

what is the penis derived from

Answer 16

genital tubercle

Question 17

what is the scrotum derived from

Answer 17

genital swellings

Question 18

what is the prostate derived from

Answer 18

urethral epithelium

Question 19

what happens with the primitive sex cords in females

Answer 19

it degenerates

Question 20

what happens with coelomic epithelium in females

Answer 20

it expands to form the cortical region aka cortex. this happens as the medulla (primitive sex cord) degenerates

Question 21

what is important to female development in terms of hormones

Answer 21

lack of DHT and MIH

Question 22

what do the mesonephric ducts become in males

Answer 22

epididymis, ductus deferens, seminal vesicles, ejaculatory duct

Question 23

what do mesonephric tubules become in males

Answer 23

efferent tubules

Question 24

what do paramesonephric ducts become in males

Answer 24

not much; partially the appendix testis and prostatic utricle

Question 25

what do the mesonephric ducts become in females

Answer 25

mostly degenerate, but can form gartner's duct/cyst and the appendix of the ovary

Question 26

what do mesonephric tubules become in females

Answer 26

largely degenerate, but partially epoophoron and paraoophoron

Question 27

what do the paramesonephric ducts become in females

Answer 27

uterine tubes, uterus, cervix, superior third of the vagina

Question 28

what helps form the uterus and upper third of the vagina

Answer 28

fusion of caudal aspects of mesonephric ducts

Question 29

when does descent of the testes begin

Answer 29

weeks 10-14

Question 30

when is descent of testes complete

Answer 30

can finish after birth, but usually descend into the scrotum during the 7th month

Question 31

what pathway do the testes take into the scrotum

Answer 31

a retroperitoneal pathway

Question 32

what guides the descent of the testes

Answer 32

the gubernaculum

Question 33

the descent of the testes forms which structures

Answer 33

deep ring, inguinal canal, and superficial ring

Question 34

what happens if there are defects in the processus vaginalis

Answer 34

herniation of abdominal contents (indirect hernia) if it is completely patent, hydrocele if partial

Question 35

what stabilizes the ovaries cranially

Answer 35

suspensory ligament of the ovary

Question 36

what stabilizes the ovaries caudally

Answer 36

round ligament of the ovary

Question 37

what does the urogenital sinus form

Answer 37

bladder, urethra, vaginal vestibule

Question 38

what does the mesonephric ligament form in males

Answer 38

gubernaculum testis

Question 39

what does the mesonephric ligament form in females

Answer 39

round ligament of the ovary/uterus

Question 40

what does the genital tubercle form in males

Answer 40

penis

Question 41

what does the genital tubercle form in females

Answer 41

clitoris

Question 42

what do genital folds form in males

Answer 42

floor of penile urethra

Question 43

what do genital folds form in females

Answer 43

labia minora

Question 44

what results from congenital adrenal hyperplasia

Answer 44

female pseudohermaphroditism

Question 45

what causes testicular feminization

Answer 45

androgen insensitivity

Question 46

what is hypospadias

Answer 46

opening of urethra on the ventral surface of the penis due to urethral folds not closing properly

Question 47

what is epispadias

Answer 47

opening of the urethra on the dorsal surface of the penis