Reproductive: Anatomy and Development

Question 1

Gonads differentiate into what in male and female?

Answer 1

male: testes, semineiferous tubules, rete testes
female: ovary, follicles, rete ovarii

Question 2

Male and female: paramesonephric ducts differentiate into what?

Answer 2

Male: appendix of testes

female: uterine tubbes, uterus, cervix, upper vagina

Question 3

Mesonephric ducts differentiation

Answer 3

Male: epididymis, ductus deferens, seminal vesicle, ejaculatory duct

Female: Duct of gartner

Question 4

Phallus differentiation

Answer 4

Male: glans and body of penis

Female: clitoris

Question 5

urogenital folds differentiation

Answer 5

Male: ventral aspect of penis

Female: labia minora

Question 6

Labioscrotal swellings differentiation

Answer 6

Male: scrotum

Female: Labia majora

Question 7

What is the most common cause of female pseudointersexuality?

Answer 7

congenital adrenal hyperplasia => fetus produces excess androgens

Question 8

What is the most common cause male pseudointersexuality?

Answer 8

5a-reductase deficiency causes inadequate production of testosterone and MIF by fetal testes

Question 9

What does female pseudointersexuality look like grossly?

Answer 9

ovarian (but no testicular) tissue;

masculinization of female external genitalia

Question 10

What does the male pseudointersexuality look like grossly?

Answer 10

testicular (not ovarian) tissue and stunted development of male external genitalia

Question 11

What is the result of a 5a-reductase 2 gene mutation?

Answer 11

5a-reductase enzyme is underactive in catalyzing conversion of testosterone to DHT

Question 12

What are the clinical findings of 5a-reductase 2 deficiency?

Answer 12

underdevelopment of penis/scrotum and prostate gland => microphallus, hypospadias, bifid scrotum

Question 13

What happens in complete androgen insensitivity?

Answer 13

occurs when fetus w/ 46, XY develops testes and female external genitalia w/ rudimentary vagina => uterus/tubes are generally absent

Question 14

Where are the testes located in complete androgen insensitivity?

Answer 14

found in labia majora => surgically removed to circumvent malignant tumor formation

Question 15

What is the most common cause of complete androgen insensitivity?

Answer 15

mutation in androgen receptor (AR) gene rendering AR inactive

Question 16

What is the gross phenotype of complete androgen insensitivity?

Answer 16

normal appearing females and psychosocial orientation is female despite phenotype

Question 17

What causes a female with complete androgen insensitivity to go to the physician?

Answer 17

at puberty, undergo virilization due to increased T:DHT ratio

Question 18

What forms the floor of the pelvis?

Answer 18

pelvic diaphragm (2 layers of fascia with middle layer of muscle)

Question 19

What are the muscles that make up the pelvic diaphragm’s middle layer?

Answer 19

levator ani and coccygeus

Question 20

What is the action of the levator ani?

Answer 20

muscular sling for rectum;

boundary between rectum and anal canal

Question 21

What does the region below the pelvic diaphragm contain?

Answer 21

perineum contains the ischioanal fossa

Question 22

What does the ischioanal fossa contain?

Answer 22

fat filled region below pelvic diaphragm surrounding anal canal

Question 23

Where is the urogenital diaphragm? composed of what?

Answer 23

perineum and extends between the 2 ischiopubic rami;

2 layers of fascia w/ middle layer of skeletal muscle

Question 24

What is the deep perineal pouch?

Answer 24

middle (muscle) layer of the urogenital diaphragm

Question 25

What can be found in the deep perineal pouch?

Answer 25

sphincter urethrae muscle;
deep transverse perineal muscle;
Bulbourethral (Cowper) gland (male only)

Question 26

Action of sphincter urethrae muscle

Answer 26

serves as external sphincter of urethra

Question 27

Describe the bulbourethral gland

Answer 27

duct that enters the bulbar urethra

Question 28

What is the superficial perineal pouch?

Answer 28

below UG diaphragm and enclosed by superficial perineal colles fascia

Question 29

What does the superficial perineal pouch contain?

Answer 29

crura of penis or clitoris;
bulb of penis (male) or bulb of vestibule (female);
Ischiocavernosus muscle;
bulbospongiosus muscle;
greater vestibular (Bartholin) gland (female)

Question 30

What is the function of the crura of penis/clitoris?

Answer 30

erectile tissue

Question 31

function of bulb of penis

Answer 31

erectile tissue; contains urethra

Question 32

function of vestibule

Answer 32

erectile tissue; lateral walls of vestibule

Question 33

function of ischiocavernosus muscle

Answer 33

skeletal muscle that covers crura of penis/clitoris

Question 34

function of bulbospongiosus muscle

Answer 34

skeletal muscle that covers bulb of penis/vestible

Question 35

function of vestibular (Bartholin) gland

Answer 35

homologous to Cowper gland

Question 36

What innervates the skeletal muscles in pelvic and UG diaphragms?

Answer 36

Pudendal nerve and branches (S2, S3, S4 ventral rami)

Question 37

What does the pudendal nerve innervate within the pelvic and UG diaphragm?

Answer 37

external anal sphincter;
sphincter urethrae;
skeletal muscles in both perineal pouches;
skin that overlies perineum