Assigned Male at Birth Reproductive Anatomy Flashcards
Describe overal anatomy
Has components in abdomen, pelvis and perineum
Is a series of ducts, and tubules, linked to urinary tract
name gonad related structures
Scrotum
Testes
Epididymis
Name ducts structures
Vas deferens - long tube, connects external component to internal associated glands
Ejaculatory ducts
Penis and erectile tissue
Urethra = links to urinary
Name accessory glands
Secrete fluid, combine with sperm and produce semen
Seminal vesicles
Prostate
Bulbourethral glands
What is scrotum
Superficial component of genital organ with penis
Homologous to labia Majora in female
Dual chambered sack of skin and smooth muscle
Describe musculofascial covering
Tunica dartos muscle = subcutaneous, muscle layer, thin smooth muscle, on top of spermatic cord
Describe role of musculofascial covering
Regulate scrotal temp = optimal temp for spermatognesis
What gives scrotum wrinkled appearance
Contraction of tunica dartos = wrinkled appearance, - goal = reduce surface for heat loss, increases surface area
Describe paminiform plexus
Ensheath testiscualr artery
Network of small spermatic veins in spermatic cord
Series of veins
Drain into testicular vein —> varicocele
What is scrotum composed of
Musculofascial covering
Pampiniform plexus
What is role of pampiniform plexus
Regulate temp fo testes =temp of blood warm to would reabsorb heat to lower blood temp of blood going to testes
When is spermatogenesis optimal
1-1.5 degrees below core body temp
If too warm = no spermatogensis
What is a varicocele
Varicose of pampiniform plexus
Renal vein stuck between abd aorta and Sma
Describe stats of varicoceles
The cause of 17-21% of infertility in ppl
90% of anatomical caused infertility
Compromises spermatogenesis since less heat absorbed when it’s going up
What is spermatic cord
Cord like structure that passes through inguinal canal, links outside to inside
Allows communication between abdomenopelvic cavities to testes, via inguinal canal
What does spermatic cord contain
Paminiform plexus, testicular artery, vas deferens, testicular innervation
Describe embryology of testes
Originally develop high on post abd wall - at level of kidneys in adults
Descend before birth through inguinal canal, forming spermatic cord, to scrotum of perineum
During descent = bring nerve, blood supply, drainage and vas deferens
(In female = stops in pelvis)
What are testes enclosed in
Within the end of elongated musculofascial pouch projecting into scrotum
Continuous with anterior abd wall via spermatic cord
describe all layers of spermatic cord - gen
Dragged down peritoneum and layers of abd cavity = form layers
Describe what ext oblique muscle aponeurosis forms = layer in spermatic cord
External spermatic fascia
Describe what interal oblique muscle forms = layer in spermatic cord
Cremasteric muscle - raise and lower testes for thermal regulation
Yo-yo, bring lower to lower temp, bring closer to warm up
Innervated = l1, cremasteric reflex
Describe what transversalis fascia forms = layer in spermatic cord
Internal spermatic fascia
Describe what parietal peritoneum forms = layer in spermatic cord
Tunica vaginalis
Invagination - pocket, ant surface testes, cushion and protect
Testes well innervated
Describe inguinal hernias - gen
Tissue protruding through abd wall of inguinal region
8x more common than in afab (no big structures through inguinal canal)
Describe indirect inguinal hernia
2/3
Abdominal viscera herniate through deep inguinal ring to scrotum
Bowels stuff scrotum, = bad
More problematic= cause strangulation
More common in middle aged and older men, risk of bowel obstruction and strangulation
Need surgical intervention
Describe direct inguinal hernia
1/3
Abd viscera herniate though inguinal triangle - hesselbachs, = inferior epigastric vessel, rectus abdominus, inguinal ligament
Weak point in wall
Sport hernia
Less change of bowl obstruction since open space - less chance strangulation
Describe testes
In scrotum
Covered by a closed sac of peritoneum = tunica vaginalis - anterior, infront
Thick testicular capsule = tunica albuginea- fibrotic, hard
Name parts of internal anatomy of testes
Seminiferous tubules
Rete testes
Epididymis
Describe seminiferous tubules
Site of spermatogenesis —> to rete testes
Describe rete testes
Collecting chamber - reabsorption of fluid to increase sperm concentration
Network - helps concentrate sperm
Links to epididymis
Describe epididymis
Long coiled duct in scrotum, posterior side, mobile
Role = maturation of spermatozoa and storage - 2-3 months
Bridges inner testes to duct system
Name and describe parts of epididymis
Head = efferent ductules from enlarged coiled mass
Body = run along posterolateral aspect of testis
Tail = found on inf pole testes, continuous with vas deferens
What is vas deferens
Floppy tube, link outside to inside
Long muscular tube
Transport spermatozoa: epididymis —> ejaculatory duct
Describe path of vas deferens
Through spermatic cord- inside abd cavity to pelvic cavity —> Loop lateral to inferior epigastric artery —> Enters pelvic inlet -> Retroperioneal —> passes over ureters —> dives inferomedially along base of bladder —> Gets enlarged- ampulla of vas deferens —> Joins seminal vesicle to form ejaculatory duct
Describe what suspends vas deferens
Over inferior epigastric Artery and then reaches post aspect bladder, then suspended by ureter
Describe seminal vesicle
Paired accessory glands of male reproductive system
Coiled tube situated between bladder and rectum
Lateral to ampulla of vas deferens at base of bladder
Secretes most of fluid, first gland, behind bladder
what is role of seminal vesicle
Secrete most of fluid that becomes semen
High in fructose concentration —> sugar boost, hyper
Joins ductus deferens to form ejaculatory duct
Describe ejaculatory duct
Prepare for ejaculation, sperm and spermatozoa stored and accumulated in vas deferens ampulla
Peristaltic contractions to move sperm
Drains into prostatic urethra
Describe prostate
Base of bladder
Unpaired accessory gland of male repro system
Surrounds urethra = prostatic urethra
Lies immediately inferior to bladder and superior to pelvic floor
What is prostate composed of
Individual glandular complexes
All in same capsule
All emptying into prostatic urethra through individual openings
Describe prostate Role
Secrete slightly alkaline fluid to neutralize acidity of vasginal tract - help it survive
Describe prostate - openings, inside
Ejaculator duct openings - 2
Fructose rich and sperm mix and meet - add alkaline fluid
Describe prostate - clinical correlate
Most common cancer among men
21% of all cancer in Canada, 2023, 5 year net survival = 91%, but consider quality of life
Palpate= trans anally - posterior lobe of prostate = lobe most prone to cancer
Describe bulbourethral glands - Gen
Cowper’s
Paired accessory glands of male reproductive system
Situated in deep perineal pouch (between levator ani and perineal membrane)- (diff for afab, bartholins not in pouch)
Small pea shaped mucous glands
Located behind membranous urethra
Ducts of glands pass through perineal membrane
Drains into urethra of root of penis
Describe bulbourethral glands - role
Pre ejaculatory emiission to neutralize acidic urine and lurbriact e uretha - make good environment for sperms
Pee can be acidic
Describe erectile tissue
Composed of 2 corpora cavernosa - hollow, receive blood during erection
1 corpus sponging - contains urethra, spongy tissue
All contained in thick fascia = deep fascia of penis = bucks fascia, tough ct
Name components of erectile tissue
Root of penis = crura and bulb
Body pf penis
Glans
Describe root of penis
Bulb and Crura
Describe crura - root of penis
2 crura = proximal parts of corpora cavernosa - root of, attached to inferior pubic rami
Describe bulb - root of penis
1
Proximal part of corpus spongipsum
Anchored to perineal membrane - centrally located
Describe body of penis
No longer anchored =
Formed by free part of corpora cavernosa and corpus spongiosum
= where will erect
Describe glans of penis
Expansion fo corpus spongiosum over beyond distal end of corpora cavernosa
Name skeletal muscles
Ischiocavernosus
Bulbospongiosus
Describe ischiocavernosus
Cover crura of penis
Anchored to ischial tuberosity and inferior pubic Rami
What is role of ischiocavernosus
Forces blood from crura into body pf penis for erection
Describe bulbospongiosus
Covers bulb of penis
Anchored for perineal body and perineal membrane
Describe role of bulbospongiosus
Forces blood into distal region fo penis
Emptying urethra During voiding
Pulsatilla emission of semen during ejaculation
Make sure pressure if good, contract and move blood to penis
What is innervation of skeletal muscles of penis
Somatic - pudendal nerve, s2-4
Describe blood supply of penis
3 branches of internal pudendal artery
Artery of bulb of penis = supplies bulb
Dorsal penile artery runs along dorsum fo penis
Deep penile artery = runs within corpus cavernosum
Describe venous drainage of penis
One vein = deep dorsal vein
Passes under pubic symphysis,joins prostatic plexus
Outside corpus cav but deep to bucks fascia
Describe erection - specifics
Vascular event generated by parasympathetic fibres= from pelvic splanchicn, s2-s4
Relaxation fo branches of deep penile arteries = vasodilation
Corpus cavernosum engorge
Contraction of ischiocavernosus and bulbospongiosus = force blood into distal region of penis, deep dorsal vein compressed under bucks fascia = impede venous outflow = erection
Describe erection - Gen informal
Psns = have arteries vasodilate and blood - cavernosum filled with blood, so increase pressure inside bucks fascia (unstretchable) - so only venous drainage system of inner component of penis compressed = vein compressed under bucks fascia and muscles push more blood = erection
Describe male urethra
Long - 20cm
From neck of bladder to external urethral orifice
Passes through prostate, deep perineal pouch, perineal membrane and penis
Name all parts of urethra
Preprostatic urethra
Prostatic part
Membranous part
Spongy urethra - penile
What is internal urethral sphincter
Between bladder and prostate
Describe preprostatic urethra
1cm
Along base of bladder to prostate
Internal urethral sphincter= prevents retrograde ejacultion
Describe prostatic part
3-4 cm
Surrounded by prostate
Where ejaculatory and glandular complexes empties
Describe membranous part
Narrower
Passes through deep perineal pouch
Surrounded by external urethral sphincter
Jucntion between prostate and penis
Describe spongy urethra - penile
Within corpus spongiosum
Bulbourethral glands empty into bulb region
Ends at external urethral orifice
Describe peritoneum
Peritoneum of abdominal cavity is continuous through pelvic inlet
Drapes over pelvic viscera:
Forms: pouches between viscera, and ligaments
Describe peritoneum in males
Drapes over bladder and seminal vesicles
Reflects not anterior aspect of rectum
Describe clinical correlate - peritoneum amab
Inflammation of infection of peritoneal cavity causes fluid to accumulate here in amab - rectovesicle pouch
What is sexual response
Erection, emission, ejaculation
Involves sympathetic, parasympathetic and somatic pathways
Describe erection
Parasympathetic innervation: relaxation of deep penile arteries
(Constriction maintained by sympathetic innervation)
Pudendal nerve: Contraction of bulbo & ischiocavernosus -> force blood into erectile tissue
Describe emission
Parasympathetic stimulation mediates secretion of seminal fluid
Sympathetic stimulate peristalsis movement of ductus deferens & seminal vesicle glands
Fluid is propelled into prostatic urethra where prostatic fluid is added
Describe ejaculation
Sympathetic stimulate constriction of internal urethra sphincter (prevent retrograde ejaculation)
Strong pulsatile contraction for ejaculation: Parasympathetic stimulation contracts urethral muscle, Pudendal nerve contracts bulbospongiosus
Describe internal urethral sphincter role specifically
Semen could go up to bladder - type of infertility, can happen after prostate surgery
Sphincter closes and makes only one path out
Describe semens pathway
Seminiferous tubules —> straight tubule —> Rete testis —> Efferent ductules —> Epididymis — ductus deferens —> Ejaculatory duct —> prostatic —> Membranous —> Penile urethra
Describe recto vesicular pouch
Space between rectum and bladder
Lowets part of peritoneal cavity (equiv to afab recto uterine pouch)
On top of rectum and bladder
