1) Development of Reproductive Systems

Question 1

What are the male internal genitalia?

Answer 1

Testis
Duct: epididymis, vas deferens and urethra
Seminal vesicles, prostate and bulbo-urethral glands

Question 2

What are the male external genitalia?

Answer 2

Penis

Scrotum

Question 3

What are the female internal genitalia?

Answer 3

Ovaries

Duct: fallopian tube, uterus, cervix and vagina

Question 4

What are the female external genitalia?

Answer 4

Vagina
Vestibule
Clitoris
Labia majora and minora

Question 5

What are some male secondary sexual characteristics?

Answer 5

Increased body size
Facial hair
Male pattern baldness

Question 6

What are some female secondary sexual characteristics?

Answer 6

Pubic and axillary hair
Subcutaneous fat distribution
Breast development

Question 7

What is the gonad derived from?

Answer 7

Intermediate mesoderm

Question 8

What is the path of the primordial germ cells?

Answer 8

From yolk sac migrate to retroperitoneum via dorsal mesentery, to interact with the gonad

Question 9

A primordial germ cell tumour develops, what is the likely causative mechanism?

Answer 9

Germ cells get ‘lost’ on their path to gonad

Question 10

How do germ cells form gametes?

Answer 10

Multiply by mitosis and then undergo meiosis

Question 11

What genes drive development of the male?

Answer 11

SRY genes on Y chromosome

Question 12

What is the effect on SRY gene expression on the gonad?

Answer 12

Formation of testis

Medullary cords in gonad and thick tunica albuginea

Question 13

What does absence of SRY gene expression lead to?

Answer 13

Formation of ovary

Cortical cords develop in gonad

Question 14

Why does female gonad have no tunica albuginea?

Answer 14

Facilitates ovulation

Question 15

What do the male internal genitalia form from?

Answer 15

Wolffian or mesonephric ducts

Question 16

What do the female internal genitalia form from?

Answer 16

Mullerian or paramesonephric ducts

Question 17

What causes mesonephric duct to remain?

Answer 17

Testis derived testosterone

Question 18

What causes paramesonephric duct to regress?

Answer 18

Testis derived Mullerian inhibiting substance

Question 19

What do Sertoli cells release?

Answer 19

Mullerian inhibiting substance

Question 20

What do the mesonephric ducts form?

Answer 20

Epididymis, vas deferens and seminal vesicle

Question 21

What do the paramesonephric ducts form?

Answer 21

Fallopian tubes, uterus, cervix and upper third of vagina

Question 22

What does the urogenital sinus form?

Answer 22

Lower two thirds of vagina

Question 23

What do genital swellings and urethral folds form in females?

Answer 23

Labia majora and minora respectively

Question 24

What does the genital tubercle form in the female?

Answer 24

Clitoris

Question 25

What causes the urethral folds to close in the male and what does this fusion form?

Answer 25

Androgens secreted by testis (dihydrotestosterone) | Shaft of penis

Question 26

What do genital swelling form in males?

Answer 26

Scrotum

Question 27

What does the genital tubercle form in males?

Answer 27

Elongates to form glans penis

Question 28

What does the gubernaculum become in females?

Answer 28

``` Ovarian ligament (ovary to uterus) Round ligament (uterus to labia) ```