Dev. of Reproductive

Question 1

What do the somatic support cells become in the male and female?

Answer 1

• Male: sertoli
• Femae: follicle

Question 2

Where do the genital ducts form?

Answer 2

In the intermediate mesoderm of the urogenital ridge

Question 3

What is the mesonephric duct, and what are its derivatives?

Answer 3

• Part of early kidney development
• Epididymis, vas deferens, seminal vesicles, ejaculatory duct

Question 4

What are the derivatives of the paramesonephric duct?

Answer 4

Oviduct, uterus, upper vagina

Question 5

What happens with the SRY gene, when is it active, where is it found?

Answer 5

Development becomes male

• only active from days 41-52 and expressed in the somatic support cells
• Upregulates testis specific genes

Question 6

What cells help organize seminiferous tubules?

Answer 6

Sertoli cells that surround primordial germ cells

Question 7

What stimulates the production of anti mullerian hormone? What does AMH cause?

Answer 7

• SRY gene stimulates the TF Sox9 which stimulates AMH causing the regression of the paramesonehpric duct btw weeks 8-10

Question 8

What drives the mesonephric ducts to form their derivitives and what are they?

Answer 8

• Leydig cells producing testosterone
• Forms efferent ductules
• Epididymis
• Vas deferens
• Seminal vesicles

Question 9

In the male when the paramesonephric duct regresses what is left behind?

Answer 9

• Utricle
• Appendix epididymis

Question 10

Describe Fetal Leydig cells.

Answer 10

• They’re only present in fetal life, they regress in fetal/early postnatal life
• Produce testosterone around weeks 8-12 driven by hCG from the placenta to form the mesonephric duct

Question 11

What does 5-a hydroxylase do?

Answer 11

• Converts testosterone into dihydrotestosterone which will cause:
  
  • Genital tubercle to develop into the penis
  • Genital swellings to develop into scrotum
  • Urethral epithelium to develop into prostate

Question 12

What do adult leydig cells do?

Answer 12

responsible for androgen production causing initiation of spermatogenesis at puberty and masculinization of brain and sexual behavior

Question 13

Where does the seminal vesicle and vas deferens come from?

Answer 13

Buds from mesonephric duct in the intermediate mesoderm of the urogenital ridge

Question 14

Where does the prostate gland bud from?

Answer 14

Endoderm of urogenital sinus in region of the pelvic urethra around week 10

Question 15

Where do bulbourethral glands come from?

Answer 15

Endodermal buds

Question 16

What is the genital tubercle?

Answer 16

• ectodermal covered mesodermal swelling at ventral and cranial end of phallic portion of urogenital plate

Question 17

What is the glans plate?

Answer 17

remnanats of cloacal membrane at the ventral end of the urogenital plate and adjacent genital tubercle

Question 18

What is the urogenital plate?

Answer 18

Rupture of the cloacal membrane opening the phallic portion of the urogenital sinus to exterior forming endodermally lined platej

Question 19

How does DHT impact labioscrotal swellings and genital tubercle?

Answer 19

It drives the lengthening and growth of genital tubercle and fusion of the labioscrotal swellings to form scrotum

Question 20

When does the urethra close?

Answer 20

week 14

Question 21

What is hypospadias?

Answer 21

Most common birth defect in males after cryptorchidism, failure of the urethral fold to close fully

Question 22

What is epispadias

Answer 22

Genital tubercle forms inferior to glans plate and urethra opens superior to penis, rare

Question 23

In the absence of SRY gene, what drives ovarian development?

Answer 23

WNT-4 and FOXL2

• Constant expression of FOXL2 suppresses SOX-9 development which maintains the female gonad development

Question 24

In absense of SRY what do primordial germ ccells differentiate into and what about the somatic support cells

Answer 24

Oogonia which proliferate and differentiate into oocytes and follicle cells surrounds surround oocytes blocking meiosis I

Question 25

In the absence of sertoli and leydig cells in women, what occurs?

Answer 25

NO AMH is produced so the paramesonephric ducts are retained and mesonephric duct system is lost

Question 26

What happens during weeks 9-10 in uterus formation?

Answer 26

Fusioin of the inferior paramesonephric ducts form the uterus and uterine tubes are unfused superior portion of the paramesonephric ducts

Question 27

How does the vagina form?

Answer 27

Forms from lengthening of solid sinuvaginal bulbs which come from endoderm, and it eventually canalizes

Question 28

What does the vaginal fornix form from?

Answer 28

Fussed paramesonephric ducts (mesoderm)

Question 29

What causes vaginal agenesis?

Answer 29

failed sinovaginal bulb development &/or canalization

Question 30

In the female what is the phallic segment of the urogenital sinus made of?

Answer 30

* Urogenital plate * Glans plate * Genital tubercle

Question 31

glans clitoris forms from what?

Answer 31

genital tubercle

Question 32

How does the broad ligament form??

Answer 32

* Midline fusion of paramesonephric ductrs brings the urogenital ridge within the pelvic cavity and its covered with peritoneum * When the uterus is formed the tissue thins forming double fold of peritoneum supporting the uterus and ovary

Question 33

Round ligament of ovary connecting it to uterus develops from \_\_\_.

Answer 33

Superior gubernaculum

Question 34

Round ligament of uterus connecting uterus to labia majora forms from \_\_\_\_.

Answer 34

Inferior gubernaculum

Question 35

Patient has genotype of 46,XY and has testis but phenotype is female. What could it be?

Answer 35

Could be: * Inadequate production of testosterone * Androgen insensivity syndrome * 5-alpha reductase deficiency (cant go from testosterone to DHT) * Mutations in AMH hormone or receptor

Question 36

What is androgen insensitivity syndrome in males?

Answer 36

* X linked recessive * Male may have testis but no spermatogenesis and testosterone levels may be high due to lack of NFB bc body can't detect testesterone * At puberty testosterone is metabolized to estradiol initiating female seocondary characteristics but patients exhibit amenorrhea * Testes usually found in inguinal or labial regions * Has increased risk of tumor formation in gonads

Question 37

What is 5-alpha reductase deficiency in males?

Answer 37

* XY 46 genotype * Auto recessive * Normal testis and duct system, could make AMH and testosterone * Underdeveloped male external genitalia due to lack of DHT * depending on level of deficiency patient can exhibit external female phenotype

Question 38

Female congenital adrenal hyperplasia?

Answer 38

* Fetus produces excess androgens resulting in masculinizaton of female external genitalia * could result in labia fusing * Congenital adrenal hyperplasia is most common cause of female sexual ambiguity * deficiency in 21 hydroxylase