embryology pelvis (funk) Flashcards
what mesoderm forms the reproductive hormones
intermediate mesoderm
paramesonephric duct forms what
fmeale internal repro organs
this degenerates in the male b/c of AMH
mesoneprhic duct forms what
male internal repro organs
genital ridge forms what
gonad
what is the importance of primordial germ cells
migrate to the genital ridges by week 4-6 and if they dont migrate no gonads form
what does TDF do
its producted from SRY transcription factor
induces the indifferent gonad to form the testes
when do the testes secrete testosteron
week 8
what does the medulla of the primitive gonad form
testes
what does the cortex of the primitive gonad form
tunica albuginea
what controls descent of testes
testosterone
what is the gubernaculum
thick ligament that attaches the caudal pole of the testes to the anteiror body wall
processus vaginalis
evaginagtion of peritoneum
what does the tunica vaginalis come form
processus vaginalis
forms a cavity around the testes
what are the layers starting from INSIDE the testes to the outside
tunica albuginae visceral tunica vaginalis parietal tunica vaginalis internal spermatic fascia (aka transversalis fascia) cremastor muscle (internal abdominal oblique) external spermatic fascia Colle's (scarpa's) Dartos
what duct system does testosterone act on
wolfian duct (mesonephric) to differentiate into male genital ducts and glands (ductus deferens, epididymis, seminal vesicles)
what does the urethra give rise to
prostate and bulbourethral glands
what is the prostatic utricle
a small portion of the paramesonephric duct that regressed
when are the external genitalia fully developed
12 week
what are cloacal folds
divides into anal and urethral folds whicheventually form anus and shaft, root of penis and penile urethra
what does the genital tubercle form in males
glans penis
what do labioscrotal swellings form
scrotum
fuse midline
hypospadias
caused by incomplete fusion of the urethral groove on ventral surface of penis
too low testosterone can cause this
epispadias
urethral opening on dorsum of penis
often occurs with exstrophy of the bladder
doesn’t depend on testosterone
thought to be due to urethral plate developing more dorsally than normal
hydrocele
fluid around scrotum cause by excessive serous fluid within tunica vaginalis
cryptorchidism
failure of testes to descend into scrotum
testosterone dependent
infertility can ensue b/c too hot!!
increased chanced of cancer
in the absence of TDF what occurs
female indifferent gonad forms and the sex cords in the medulla degenerate
a second generation of cortical sex cords form from the epithelium and these will form the follicular cells around the oogonia
internal and external female genitalia form in the absence of hormonal input
what portion of the primitive gonad forms the ovary
cortex
medulla regresses
what does the gubernaculum form in the female
will form the ovarian ligament and round ligament
is there a processus vaginalis in females
yes but very small and obliterates before birth
what does the cranial end of the paramesonephric duct form
uterine tube not fused (probably infundibulum area)
what does the caudal fused portion of the paramesonephric duct form (3)
uterus, cervix and superior vagina
what forms the inferior vagina
the vaginal plate (sinovaginal bulb)
when does the vaginal plate canalize
5th month
what does the urethral endoderm form
greater vestibular and skene’s glands
what does the gential tubercle form in females
clitoris
what do the urethral folds form in adult female
labia minora
erectile tissue–> bulbs of vestibule and crus of clitoris
urethral groove remains unfused and will form the vestibule
what do the labioscrotal swellings form
labia majora
what is the cause of most congenital anomalies of the female reproductive tract
incomplete fusion of the two paramesonephric ducts
uterus arcuatus
very slight lack of fusion of paramesonephric ducts
double uterus with double vagina (uterus didelphys)
complete lack of fusion of paramesonephric ducts and formation of two sinovaginal bulbs
uterus bicornis
partial lack of fusion of paramesonephric ducts
uterus unicornis
complete agenesis of one paramesonephric ducts
uterus bicornis unicollis
caudal portion of 1 paramesonephric duct fails to form
vaginal and cervical atresia
atresia of the sinovaginal bulbs or from a failure of canalization
what is the epoophoron
remnant of mesonephric tubule
can become cystic
what is hthe paroophoron
remnant of tubules and ducts (mesonephric)
can become cystic
what is gartner’s duct
remnant of caudal mesonephric duct
can become cystic
Klinefelter syndrome
47 XXY male
nondisjuntion
testes form but are infertile (aspermatogenesis) due to low testosterone levels
impaired sexual maturation
gynecomastia (moobs)
Turner syndrome
45 XO (missing X)
nondisjunction cause
gonadal dysgenesis streak gonads (no gonads)
b/c ovaries are not required for internal and external genitalia formation female external and internal genitatlia (not ovaries) are normal
lack of secondary sex traits at puberty (no ovaries and no estrogen)
short stature, broad chest, short neck
lymphedema of hands and feet , amenorrhea
very similar to swyer
swyer syndrome
46 XY
cause–> point mutation of SRY gene resulting in defective TDF (y chromosome is not funcitonal)
presents very similar to turner
gonadal dysgenesis, streak gonads, can become cancerous
female external and internal genitalie (except for ovaries)
amenorrhea
no ovaries
hermaphroditism
male and female gonadal tissue
ovotestes - ovarian and testis tissue found in same gonad
most have 46 XX genotype
cause is most likely translocation of a portion of Y (containing SRY gene) onto X chromosome during meiosis
ambiguous external genitalia
female hermaphroditism
46 XX
cause –> congenital adrenal hyperplasia
excessive production of androgens
ovaries form (due to absence of TDF)
internal reproductive orangs usually females
masculinization of external genitalia (due to timing of increased androgens from adrenal gland)
enlarged clitoris
male pseudohermaphroditisim
46 XY
testes form normally (normal SRY gene and TDF)
cause –> insufficient androgen production and AMH from testes (hypogonadism)
External and internal genitalia female (due to absence of testosterone and AMH)
typically grow up male
androgen insensitivity syndrome
46 XY
testes form due to normal funcitoning Y chromosome
AMH and testosterone production is normal
cause is a lack of androgen receptors expression on reproductive tissues (not responsive to testosterone)
there is no mesonephric duct –> b/c it degenerates due to testosterone insensitivity
paramesonephric duct degenerates also due to presence of AMH so no female internal viscera
female external genitalie b/c these form in the absence of hormonal input
vagina is short and blind ending (no uterus)
have breast tissue b/c there is still aromatase in the periphery converting testosterone into estrogens
