Embryogenesis Ppt 1&2

Question 1

List the 2 germ cells of males and females

Answer 1

Sperm and eggs

Question 2

Supporting cells of males and females, respectively

Answer 2

Sertoli cells, follicle cells

Question 3

Sex hormone secreting cells for males and females, respectively

Answer 3

Leydig cells; theca cells

Question 4

What gene determines male sex

Answer 4

SRY gene

Question 5

Anti-mullerian hormone function

Answer 5

• degeneration of paramesonephric duct in males

Question 6

Leydig cells secrete

Answer 6

Testosterone

Question 7

Function of testosterone

Answer 7

• necessary for development of male internal genitalia

Question 8

Mesonephric duct gives rise to

Answer 8

Male internal genitalia

Question 9

During testicular development, what happens to the mesonephros

Answer 9

Regresses

Question 10

Remnant of the mesonephros gives rise to

Answer 10

Efferent duct

Question 11

Mesonephric duct gives rise to

Answer 11

Epididymis and vas deferens

Question 12

Dihydrotestosterone

Answer 12

• role in external male genitalia development
• converted by 5 alpha-reductase

Question 13

What cells produce desert hedgehog hormone

Answer 13

Sertoli cells

Question 14

Function of desert hedgehog hormone

Answer 14

Differentiation of leydig cells

Question 15

Genital tubercle turns into what structures in males and females, respectively

Answer 15

• males: glans penis
• females: clitoris

Question 16

Urogenital/genital folds give rise to what structures in males and females, respectively

Answer 16

• males: ventral aspect of the penis
• females: labia minora

Question 17

Labioscrotal/genital swellings give rise to which structures in males and females, respectively

Answer 17

• males: scrotum
• females: labia majora

Question 18

In females, the mesonephros tubules and epithelial cords…

Answer 18

Regress

Question 19

In females, the coelomic epithelium generates…

Answer 19

Cortex

Question 20

Females lack testosterone, so the mesonephric duct…

Answer 20

Regresses

Question 21

Since females lack Anti-mullerian hormone, the paramesonephric duct…

Answer 21

• doesn’t regress
• gives rise to oviduct, uterus, cervix, and part of vagina

Question 22

XY karyotype w/ mutated SRY gene

Answer 22

• dysfunctional ovary (may occur)
• female internal and external genitalia
• common in horses

Question 23

Persistent Mullerian duct syndrome

Answer 23

Sertoli cells can’t secrete AMH

(Mutation in AMH gene)

Mullerian ducts give rise to uterus, cervix, fallopian tubes

Question 24

Complete androgen insensitvity syndrome

Answer 24

Mutation in androgen receptor
- testosterone and DHT can’t activate downstream signaling

• abnormal development of male internal genitalia
• female external genitalia develops

Question 25

Freemartin (in cattle)

Answer 25

- due to presence of twins - 5% twinning rate in holstein cows - fetuses share blood supply due to fusion of chorio-allantois - female: small, non functional ovaries; develop male duct system, variation in external female genitalia, mullerian ducts degenerate (partial or full) so partial or no female internal genitalia

Question 26

Testicular descent has 2 phases

Answer 26

- transabdominal - inguinal-scrotal

Question 27

Swelling reaction

Answer 27

- enlargement of distal gubernaculum (becomes short and fat)

Question 28

Transabdominal phase

Answer 28

- testes retroperitoneal - swelling rxn - phase regulated by insulin-like 3 (ligand) protein

Question 29

What secretes insulin-like 3 (ligand) protein

Answer 29

- leydig cells - pancreas

Question 30

Inguinal-scrotal phase

Answer 30

- gubernaculum shrinks and pulls testes into inguinal region - inner visceral peritoneal layer & outer layer form vaginal process - retained testes= issue w/ insulin-like growth factor

Question 31

Testicular descent abnormalities

Answer 31

- cryptorchidism - inguinal hernia