Development of GU system Flashcards
What is the proper term for Wolffian ducts?
Mesonephric ducts
What is the proper name for Muellerian ducts?
Paramesonephric ducts
Wolffian ducts = ____. Muellerian = _____.
Male
Female
What does the metanephros duct and blastema turn into?
Kidney
What is the cloaca?
Outlet for waste
What precedes the mesonephros?
Pronephros
What does the mesonephric duct connect to during development? What grows off it?
Cloaca
Ureteric bud grows off (and eventually becomes urine collecting tubes of kidneys)
What goes on to become the functioning portion of the kidney?
Metanephric blastema
What are the pair of genital ridges?
Induce formation of sex cords to become ovary of testes. in mesonephros Happens in response to arrival of primordial germ cells
What is the indifferent stage?
At weeks 5-6. Cannot tell if embryo is male or female.
Which kidney is higher?
Left (liver is big)
What are locations of possible restriction of ureters?
- Hilum
- Crossing pelvic brim
- Entering the bladder
Where is ureter pain referred?
T10-L1. Referred to ipsilateral lower quadrant paint (inguinal region)
What does the cloaca divide into between weeks 4-6?
Urogenital sinus and rectum by the urorectal septum.
What is the allantois?
An open tube that connects to the yolk sac after two systems (urogenital and rectum) separate. Becomes a closed tube called the urachus and ultimately the median umbilical ligament in the adult.
What happens if the urachus malforms?
Can remain patent and open to the umbilicus.
What are the urethral sphincters?
External (striated, somatic control via pudendal)
Internal (detrusor, smooth muscle)
What are the types of urinary incontinence?
- Urge incontinence (detrusor muscle overactivity)
2. Stress incontinence (increased intra-abdominal pressure/ Poor resistance to urinary flow)
What results from oligo or anhydramnios?
Pulmonary hypoplasia ultimately resulting in respiratory distress and possibly death
What does the genital tubercle become in males? Females?
Males = gland of penis Females = clitoris
What does the genital folds become in males? Females?
Males = contributes to inf surface of penis Females = labia minora
What does the genital (labioscrotal) swellings become in males? Females?
Males = scrotal pouches Females = labia majora
What does the urogenital groove become in males? Females?
Males = penile urethra Females = remains open as vestibule
What is different in males from females in GU development? What is the equivalent in females?
What are they?
Fused genital folds (becomes corpus spongiosum)
Called bulb of vestibule in females
Erectile tissues
What muscles superficially cover the deep pouch? What do they do?
Ischiocavernosus and bulbospongiosus
Help maintain erection
What secretes fluid during female arousal?
Greater vestibular glands aka Bartholin’s glands
What is external female genitalia called?
Vulva
What is the line of the fusion of corpus spongiosum?
Penile Raphe
What is the line of the fusion of folds in the corpus spongiosum?
Penile Raphe
What is on the inner layer of penile foreskin?
Muscocutaneous glands for lubrication
What does the urethra pass through in males?
Corpus spongiosum
What are the corpora cavernosa?
2 columns along the front surface of the penis that engorge w/ blood during erection
What relaxes an erection?
Nitric oxide from nerve endings relax vascular and corporal smooth muscle
What nerve innervates male and female genitalia? What are the nerve roots?
Pudendal
S2-4
What is hypospadius?
Abnormal penile morphology where the urethra opens along the ventral surface of the penile shaft.
What is epispadias?
Opening of penile urethra on dorsal surface
What degenerates in female internal genitalia? What takes over?
Mesonephros degenerates (in the absence of testosterone)
Paramesonephros grows
What forms the uterus and fallopian tubes?
Paramesonephric ducts which fuse to form the uterus. The small portions that don’t for form the uterine (fallopian) tubes
What causes the descent of the ovary?
Shortening of gubernaculum
What connects the ovary to the uterus?
Ligament of ovary proper
What connects the uterus in body?
Round ligament of the uterus which connects to the labia
What are the adult remnants of the gubernaculum in the female?
Round ligament of uterus
Ligament of ovary proper
Where does fertilization occur?
In the fallopian tube (most commonly in the ampulla)
What are the first cells in a woman to develop cervical cancer?
Transition zone of cervix
What happens to the vagina during sexual arousal?
Increased blood flow inducing neurogenic transudate (extravascular fluid) to lubricate walls
What is the posterior fornix?
The barrier between the vagina and the rectouterine pouch (Pouch of Douglas)
What is the innervation of the vagina?
Visceral (parasympathetic 2/3) AND somatic (pudendal, distal 1/3)
What are the parasympathetic/sympathetic roots of the uterus and vagina?
Sympathetic = T12-L2
Parasympathetic travels in Pelvic splanchnic nerves from the sacral plexus
What is the blood supply of the uterus?
Ovarian artery (br. of aorta)
Uterine artery
Vaginal artery
What is the relationship of the ureter and the uterine vessels? What is this bundle called?
Ureter goes UNDER (water under the bridge!)
The cardinal ligament
What is the layer of peritoneum called that drapes over ovary and fallopian tube?
Broad ligament of uterus. Broken up to mesovarium (ovary), mesosalpinx (fallopian) and mesometrium
What do the ovarian vessels travel through?
Suspensory ligament of the ovary
What does the ductus deferens develop from?
Mesonephric duct
What is the remnant of the gubernaculum in adults males?
Gubernaculum testis
What is the path of sperm?
Seminiferous tubules -> rete testes -> efferent ductules -> epididymis (storage and maturation) - ductus deferens
What do bulbourethral glands do?
Secrete lubricant to flush out urethra just before ejaculation. Clear thick mucus
What are the parts of the male urethra?
Prostatic (prostate)
Membranous (deep perineum)
Spongy/penile (corpus spongiosum)
What is the blood supply to the male pelvis?
Anterior branch of internal iliac: Inferior vesical artery (prostratic branch, branch to ductus deferens)
Testicular artery from aorta
What supplies the skin of the scrotum and penis (& inferior anus!)?
Pudendal nerve
What is the origin of the parasympathetic nerves in the pelvis?
Pelvic Splanchnic (P+S!) S2-S3, sacral in origin
What produces penile erection?
Parasympathetic system (Point)
What produces penile ejaculation?
Sympathetic Shoot!)
What are the female descendants of the paramesonephric ducts?
Uterine tubes
Uterus
Superior vagina
What are the male descendants of the mesonephric ducts?
Epididymis
Ductus (vas) deferens
Seminal vesicles
Ejaculatory ducts
Where do internal pelvic organs drain their lymph?
Follows the pattern of venous drainage
Where do superficial pelvic organs drain their lymph?
Inguinal nodes -> external iliac nodes
Where do the gonads drain their lymph?
(ovaries and testes) Aortic nodes
What lymph nodes do the skin of the genitalia drain to?
Superficial inguinal
