Embryology

Question 1

What mesoderm goes on to form the urogenital system?

Answer 1

Intermediate mesoderm

Question 2

In which region of the body does pronephros form?

Answer 2

Cervical region

Question 3

In which region of the body does mesonephros form?

Answer 3

Thoracolumbar region

Question 4

In which region of the body does metanephros form?

Answer 4

Pelvic region

Question 5

What structure in the embryo acts as a common opening for the gut tube and urogenital system?

Answer 5

Cloaca

Question 6

What does the cloaca divide to form?

Answer 6

Rectum

Urogenital sinus

Question 7

What does the mesonephric duct drain into?

Answer 7

Urogenital sinus

Question 8

What structure does the allantois extend from?

Answer 8

Cloaca

Question 9

What does the allantois degenerate into?

Answer 9

Urachus (Median umbilical ligament)

Question 10

What does the gonadal ridge form from?

Answer 10

A thickening of mesonephros

Question 11

What forms the indifferent gonad?

Answer 11

Germ cells migrating from yolk sac, that embed into primitive sex cords (from genital ridges)

Question 12

What forms the paramesonephric duct?

Answer 12

Epithelium envaginating from the mesonephric duct

Question 13

Which duct (mesonephric / paramesonephric) degenerates in male gonad formation?

Answer 13

Paramesonephric (Mullerian) duct

Question 14

Which duct (mesonephric / paramesonephric) degenerates in female gonad formation?

Answer 14

Mesonephric (Wolffian) duct

Question 15

What structure forms the epididymis, vas deferencs and seminal vesicle in males?

Answer 15

Mesonephric duct

Question 16

What structure forms the bladder, urethra and prostate in males?

Answer 16

Urogenital sinus

Question 17

What structure forms the fallopian tube, uterus, cervix in females?

Answer 17

Paramesonephric duct

Question 18

What structure forms the bladder and lower part of the vagina?

Answer 18

Urogenital sinus

Question 19

What gene in males develops the indifferent gonad into a testes?

Answer 19

SRY gene

Question 20

What protein does SRY encode for?

Answer 20

TDF (testis determining factor)

Question 21

What do primordial supporting cells that express the SRY gene become?

Answer 21

Sertoli cells

Question 22

What is secreted by Sertoli cells?

Answer 22

Mullerian-Inhibiting-Substance

Question 23

What does MIS transform mesenchymal cells between cords to form?

Answer 23

Leydig cells

Question 24

What does MIS do to the paramesonephric duct?

Answer 24

Degeneration

Question 25

What hormone is produced by Leydig cells to form external genitalia?

Answer 25

Testosterone

Question 26

What is the default state of differentiation for the indifferent gonad?

Answer 26

Development into ovary

Question 27

What structure contracts to pull gonads into the pelvic region (and through the inguinal canal in males)?

Answer 27

Gubernaculum

Question 28

What structure does the gubernaculum form in females?

Answer 28

Ovarian and round ligament

Question 29

What are some complications of undescended testes?

Answer 29

Infertility Malignant transformation Testicular torsion

Question 30

What may degenerated mesonephros lead to in females?

Answer 30

Cyst formation

Question 31

List some anomalies of the female reproductive tract

Answer 31

Complete duplication Bicornuate uterus Septate uterus Arcuate uterus

Question 32

During which week of embryonic development does gastrulation, neurulation and somite formation occur?

Answer 32

Week 3

Question 33

Which weeks of embryonic development are concerned with organogenesis?

Answer 33

Weeks 4-8

Question 34

What happens if there is a failure of germ cell migration?

Answer 34

No gonads formed

Question 35

In males, what does the seminal vesicles develop from?

Answer 35

Outgrowth from caudal end of mesonephric duct

Question 36

In males, what does the prostate develop from?

Answer 36

Outgrowth from the urethra (from urogenital sinus)

Question 37

In females, what does the caudal end of the paramesonephric duct become?

Answer 37

Uterus and superior part of vagina

Question 38

At what stage do the testis enter the scrotum?

Answer 38

Just prior to birth

Question 39

What is the management for undescended testes?

Answer 39

Orchiopexy

Question 40

List some of the effects of teratogens?

Answer 40

``` Intrauterine death Structural (congenital) malformations IUGR or growth defects Neurodevelopmental/behaviour dysfunction Developmental delay Carcinogenesis ```

Question 41

List some facial differences in fetal alcohol syndrome?

Answer 41

- Small head - Low nasal bridge - Epicanthal folds - Smooth philtrum - Thin upper lip - Underdeveloped jaw

Question 42

What is the classical triad for congenital rubella syndrome?

Answer 42

- Sensorineural deafness - Eye abnormalities (esp. retinopathy, cataract and microphthalmia) - Congenital heart disease (pulmonary artery stenosis and patent ductus arteriosus)

Question 43

What medications may cause respiratory depression in neonates?

Answer 43

Opiate medications

Question 44

When is the greatest risk of adverse effects on teratogen exposure?

Answer 44

Weeks 3 and 11

Question 45

Where does the uterine artery pass in relation to the ureter?

Answer 45

Ureter passes under the uterine vessels

Question 46

Where does the ureter pass in relation to the bifurcation of the iliac vessels?

Answer 46

Ureter passes over bifurcation of iliac vessels

Question 47

What spinal nerves provides sympathetic supply to the ureter?

Answer 47

T10-T11

Question 48

What spinal nerves provides parasympathetic supply to the ureter?

Answer 48

S2-4

Question 49

What spinal nerves provides sensory supply to the ureter?

Answer 49

T11-T12

Question 50

What are the three constrictions of the ureter?

Answer 50

- Pelvi-ureteric Junction - Pelvic Brim - Intramural part

Question 51

What are some technical risk factors for ureteric injury in hysterectomy?

Answer 51

- High BMI - Haemorrhage - Coexistent bladder injury - inexperienced surgeon