Flashcards in Anatomy 3 Deck (36):
What week does the mesonephric duct/wolffian duct form? What layer does it form from?
the 4th week; intermediate mesoderm
What forms the genital ridge, and where does it form?
Primordial germ cells migrate from the yolk sac to the area adjacent to mesonephric kidney.
What is the other name for the pasamesonephric duct?
What do sertoli cells secrete?
testosterone and AMH
By what week is sex determined?
Where is testosterone produce and what reulgates its secretion?
Produced in leydig cells, secretion regulated by chorionic gonadotropin (placenta) and then the pituitary after week 16
What structures are formed because of dihydrotestosterone?
external: penis, scrotum, prostate, male urethra
What structures are made by testosterone?
seminiferous tubules, spermatogenesis, secondary sex characteristics
What happens if the paramesonephric ducts fail to fuse in the upper margins?
divided (septated) uterus
How would you get the formation of a double uterus/ double vagina?
if the paramesonephric ducts fuse to the urogenital sinus separately, two separate sinovaginal bulbs develop
What happens if the sinovaginal bulb does not develop a lumen?
atresia of the cervix
What happens if a mullerian duct regresses or fails to elongate?
What does the labioscrotal swelling become in male and female?
What does the genital tubercle become in male and female?
clitoris/head of penis
what does the urogenital or urethral fold become in male and female?
penile urethra, or labia minor
What forms the urethra in the male?
urogenital fold becomes excavated, forming a urethral groove. urogenital folds move towards each other creating penile urethra
What is hypospadias?
when the urethra opens onto the ventral surfae of the penis because the urogenital folds dont fuse normally
what is epispadias?
when the urethra opens on the dorsal aspect of penis
What causes testicular hydrocele?
If the tunica vaginalis does not collapse, forming a pathway between the peritoneal cavity and tunica vaginalis that fills w/ serous secretions
What is the gubernaculum become in the female?
broad ligament of the uterus (inferior part) and round ligament of the uterus (superior part)
Androgen insensitivity synrome
normal appearing female w/ undescended testes and 46xY
5a reductase deficiency
male gonads but female primary sex characteristics. but develop secondary characteristics during puberty (because testosterone works fine)
what layer does the urogenital system arise from?
the intermediate mesoderm
What are the three nephric structures?
pronephros, mesonephros, and metanephros
What weeks are the mesonephroi functional?
what initially forms the metanephros?
uretric buds from IM
Where does the body of the kidney come from embryologically?
the metanephric blastema
Where does each structure come from?
loop of henle
first 3: from metanephric blastema
collecting duct=ureteric bud
what divides the cloaca
urorectal septum (forms a urogenital sinus and anorectal canal)
What forms the two parts of the male urethra? (prosttic and penile)
the pelvic urethra forms the prostatic urethra, the urogenital folds form the penile urethra
What is the trigone from embryologically?
the mesonephric ducts NOT the ureter/ureteric bud
What is the urachus?
the fibrous remnant of the allantois (narrowing above the bladder). forms the median fold in adult
What is a urachal sinus?
when the lumen in the urachus is patent. discharge out of umbilicus
What makes up the superficial inguinal ring and deep?
opening in the aponeurosis of external oblique and transversalis fascia