Male Reproductive Organs Flashcards
Male reproductive system
has components in abdomen, pelvis, perineum
series of duct and tubules linked to urinary tract
major component: scrotum, testis, epididymus, ductus deferens, ejaculatory ducts, penis, urethra
accessory glands:
seminal vesicles
prostate, bulbourethral glands
scrotum (overview)
superficial component of genital organ
homologous with labia majora in female
dual- chambered sack of skin & smooth muscle
scrotum (musculofascial covering)
musculofascial covering:
tunica dartos muscle: subcutaneous muscle layer
role: regulate scrotal temperature
contraction wrinkled appearance of scrotum: reduces for heat loss
scrotum (pampiniform plexus)
network of small spermatic veins in spermatic cord drain
drain into testicular vein called varicocele
role: regulate temperature of the testes
spermatic cord
allows communication between abdominal pelvic cavities to testis via inguinal canal
contains pampiniform plexus, testicular artery, vas deferens, testicular innervation
inguinal canal
anterior wall: aponeurosis of ext. oblique - superficial inguinal ring
superior wall: medial crus of aponeurosis of external oblique
posterior wall: transversalis fascia- deep inguinal ring
inferior wall: inguinal ligament
Testes: embryological origin
embryological: originally develop high on posterior abdominal wall
descend before birth through inguinal canal, forming spermatic cord, to scrotum of perineum
during descent bring with them: nerve, blood supply, drainage and vas deferens
testes enclosed within musculofascial pouch, project into scrotum.
Testes: (abdominal to fascia in spermatic fascia)
external oblique muscle aponeurosis: external spermatic fascia
internal oblique muscle: cremasteric muscle (raise and lower testes)
transversalis fascia: internal spermatic fascia
Testes: anatomy of capsule
covered by closed sac of peritoneum: tunica vaginalis
originally connected to abdominal cavity - loose connection during development
thick testicular capsule: tunica albuginea
Testes: Internal anatomy
seminiferous tubules: site of spermatogenesis (production of spermatozoa)
straight tubule: connecting seminiferous tubule to rete testis
rete testis: collecting chamber: reabsorption of fluid to increases sperm concentration
efferent ductules: from rete testis through capsule to epididymus
epididymus: role, components
long coiled duct in the scrotum
role: maturation of spermatozoa & storage (2-3 months)
head: efferents ductules form enlarged coiled mass
body: run along posterolateral aspect of testis
tail: found on inf. pole of testis/ continuous with ductus deferens
ductus deferens:
long muscular tube
transport spermatozoa to ejaculatory duct
ductus deferens
long muscular tube
transport spermatozoa to ejaculatory duct
through spermatic cord in inguinal canal
loop lateral to inf. epigastric artery
enters through pelvic inlet–> retroperitoneal
passes over ureter
dives inferomedially along base of bladder
gets enlarged: ampulla of ductus deferens
join seminal vesicle to form ejaculatory duct
seminal vesicle
paired accessory glands of male reproductive system
coiled tube situated between bladder & rectum
lateral to ampulla of ductud deferens at base of bladder
role: secrete most of the fluid that becomes semen
high in fructose concetration
joins ductus deferens to form the ejaculatory duct
ejaculatory duct
drain into prostatic urethra
prostate
unpaired accessory gland of male reproductive system
surrounds urethra–> prostatic urethra
lies immediately inferior to bladder
post to pubic symphysis/ ant. to rectum
inverted cone: base at the bladder, tip on pelvic floor
individual glandular complexes
all emptying into prostatic urethra through individual openings
role: slightly alkaline fluid, neutralize acidity of vaginal tract
bulbourethral glands
paired accessory glands of male reproductive system
situated in deep perineal pouch
small pea shaped mucous glands, located behind membranous urethra, ducts of glands pasd through perineal membrane, drains into urethra of root of penis
role: pre-ejaculatory emission
neutralize acidic urine & lubricate urethra
perineal membrane
thick triangular fascial structure attached to pubic bones, post.edge is free, inserting on the midline to perineal body, overarching the urogenital hiatus
provides attachement for external genitalia
deep perineal pouch: between perineal membrane and pelvic diaphragm. contains thin muscular sheet: sphincter for urethra
perineal body: central tendon of perineum, connective tissue that muscle of pelvic floor attached
Penis (erectile tissue)
erectile tissue & associated skeletal muscles
erectile tissue: composed of 2 corpora cavernosa (corpus cavernosum)
1 corpus spongiosum (contains urethra)
all contain in buck’s fascia
penis: root, body and glans (the little flap)
root of penis:
crura: proximal parts of corpora cavernosa attached to pubic arch
bulb: proximal part of corpus spongiosum anchored to perineal membrane
body of penis: formed by free part if corpora cavernosa and corpora cavernosa
glans: expansion of corpus spongiosum over distal end of corpora cavernosa
Penis (skeletal muscles)
ischiocavernosus: cover cura of the penis, anchored to ischial tuberosity and pubic arch.
role: forces blood from the crura
bulbospongiosum:
anchored to the perineal body and the perineal membrane
role: forces blood into distal region of penis
emptying urethra during voiding
pulsatile emission of semen during ejaculation
penis (innervation)
pudenal nerve S2/4
erectile bodies (arterial)
blood supply:
internal pudendal artery- split 3 branches
artery of the bulb
dorsal penil artery: runs along dorsum of penis
deep penile artery: runs within corpus cavernosum
Erectile bodies (venous drainage)
only one vein: deep dorsal vein
passes under pubis symphysis, joins prostatic plexus
drains into external pudendal
erectile bodies (erection)
vascular event generated by parasympathetic fibers: from pelvic splanchnic (S2-S4)
relaxation of branches of deep penil arteries–> vasodilation
corpus cavernosum engorge
contracton of bulbo & ischiocarvenosus: force blood into distal region of penis
deep drosal vein is compressed under buck’s fascia
impeded outflow–> causes erection
Urethra: path and anatomy
male urethra is long, from neck of bladder to external urethral orifice, passes through prostate, deep perineal pouch, perineal membrane and penis
preprostatic urethra: long bas of bladder to prostate
internal urethral sphincter: prevents retrograde ejaculation
prostatic part: surrounded by prostate where ejaculatory duct and glandular complex empties
membranous part: narrower
passes through deep perineal pouch
surrounded by external urethral sphincter
spongy urethra: within corpus spongiosum
bulbourethral glands empty into bulb region
ends at the external urethral orifice
Peritoneum
peritoneum of abdominal cavity is continuous through pelvic inlet
draps over pelvic viscera, forms pouches between viscera, ligament between viscera & pelvic walls
male: drapes over bladder and poles of seminal vesicles, reflect on anterior part of rectum
retrovesical pouch
space between rectum and bladder
lowest part of peritoneal cavity
sexual responses (errection)
parasympathetic innervation: relaxation of deep penile arteries (constriction maintained by sympathetic inervation)
pudendal nerve: contraction of bulbo & ischiocarvernosus–> force blood into erectile tissue
sexual responses (emission)
parasympathetic stimulation mediates secretion of eminal fluids
sympathetic stimulate peristalsis movement of ductus deferens & seminal vesicle glands
fluid is propelled into prostatic urethra where prostatic fluid is added
sexual responses (ejaculation)
sympathetic stimulate constriction of internal urethra sphincter
strong pulstatile constraction for ejaculation
parasympathetic stimulation contracts urethral muscle
pudendal nerve contract bulbospongiosus
sexual responses (semen path)
seminiferous tubules, straight tubules, rete testis, efferent ductules, epididymis, ductus deferens, ejaculatory duct, prostatic, mebranous, penile urethra.
