Male reproductive system Flashcards
early development of urogenital region: general features
- embryologically closely related
- urogenital system developed from intermediate mesoderm extends along dorsal wall of embryo
- urogenital ridges form laterally to dorsal aorta as elevation of intermediate mesoderm
early development of urogenital region: part of urogenital ridge give rise to:
- urinary system from nephrogenic cords
- genital system from genital ridge
early development of urogenital region: kidney development
- 3 successive sets of kidneys appear
- develop in pelvic region and ascend to adult position on post ab wall
- dev abnormalities of kidneys and ureters common
- pronephros
- mesonephros
- metanephros
development of genital system: features
- genetic sex -> fertilisation
- male/ female morphological characteristics don’t begin to develop until 7th wk
- primordial germ cells form in wall of yolk suck, migrate to genital ridges and differentiate into oogonia/ spermatogonia
development of genital system: Y chromosome use
- SRY gene on short arm of Y chromosome needed for expression of testis- determining factor (TDF)
- > gonadal cords into seminiferous cords (primordia of seminiferous tubules)
mullerian and wolffian ducts: red/ blue
red: wolffian
blue: mullerian
wolffian ducts:
- mesonephric - epididymis, vas deferens, seminal vesicles
- male
mullerian ducts:
- paramesonephric - uterine tubes, uterus, cervix, upper 1/3 vagina
- male
development of genital system: in 8th week
- testosterone production has been established
- fetal testes produce antimullerian hormone (AMH) -> suppress dev of mullerian ducts
male organs: name groups functionally
- gonads
- ducts
- accessory sex glands
- copulatory organ
male organs: gonads
testes
male organs: ducts
- epididymis
- ductus deferens
- ejaculatory ducts
- urethra
male organs: accessory sex glands
- seminal vesicles
- prostate
- bulbourethral glands
male organs: copulatory organ
penis
scrotum: features
- cutaneous sack:
- heavily pigmented skin
- dartos fascia (smooth mm - dartos)
- scrotum internally divided by scrotal septum and ext by scrotal raphe
scrotum: muscles
- dartos: wrinkles skins
- cremaster: skeletal mm, elevates/lowers testes
testes: features and covered in
- oval paired glands
- sperm and hormones
- covered in tunica vaginalis (serous membrane from peritoneum)
- tunica albuginea (thick ct)
testes: tunica albuginea
extends inwards and divides testis into lobules (hold seminiferous tubules)
testes: Leydig cells
- space btw seminiferous tubules
- produce testosterone
testes: blood supply
- testicular aa (branch of ab aorta)
testes: lymph
- lumbar
- preaortic lymph nodes
testes: descend of testes true
- abdominal
- inguinal suprascrotal
testes: descend of testes ectopic
- prepenile
- superficial ectopic
- transverse scrotal
- femoral
- perineal
cryptochidism: absence of 1 or both testes from scrotum
epididymis: features
- tightly coiled ducts forming: head, body, tail
- site of sperm maturation, storage, propels into vas (ductus) deferens
ductus (vas deferens): features
- long muscular duct
- continues from tail of epididymis
- conveys sperm to ejaculatory ducts
- dilated portion = ampulla
eg. vasctomy:
- cutting of ductus deferens and tied of/ and burned
spermatic cord: feautres
- supporting structure of male repro system ascends from scrotum
spermatic cord: consists of
- ductus deferens
- testicular aa
- veins (pampiniform plexus)
- nerves and lymphatics
eg. varicocele
enlargement of veins in scrotum which can be seen on surface of scrotum
seminal vesicles: features
- paired seminal vesicles post on base of urinary bladder
- secrete alkaline fluid rich in fructose
seminal vesicles: unites with
ampulla of ductus deferens = ejaculatory duct which opens into prostatic part of urethra
prostate: features
- inferior to urinary bladder
- surrounds prostatic urethra
- alkaline secretion containing enzymes (PSA, amylase, protease)
- enlargement of prostate after 45 common
prostatic urethra: features
- ejaculatory ducts empty independently into post aspect of prostatic urethra
- numerous ducts open into urethra - prostatic secretions = contribute to semen formation
bulbourethral glands: features
- aka Cowper’s gland
- pea size
- paired on either side of membranous urethra, in deep perineal muscles, inf to prostate
- open into spongy urethra
- secrete alkaline fluid neutralise acid from urine
- mucus lubricating urethra and tip of penis
penis: features
- root
- body
- glans
penis: body
- 2x corpora cavernosa (dorsolateral)
- corpus spongiosum (ventral)
penis: corpora cavernosa
- erectile cavernous tissue covered by tunica albuginea
penis: corpus spongiosum
- cavernous erectile tissue
- spongy urethra
penis: glans penis formed by
corpus spongiosum
penis: blood supply
- internal pudendal aa:
- dorsal
- central
- urethral
penis: nerve supply
sacral spinal nerves (S2-4) - pudendal - deep/ superficial perineal n - post scrotal n - dorsal n of penis
blood supply: internal iliac divides into
ant and post trunk
blood supply: which trunk gives branches to supply viscera
ant trunk
blood supply: ant trunk branches
- umbilical aa
- superior vesical
- inf vesical
- middle rectal aa
- obturator
- internal pudendal
- inf gluteal aa
blood supply: inf vesical aa supplies
- bladder
- ureter
- prostate
- seminal vesicles
blood supply: internal pudendal aa
main artery of perineum
blood supply: testicular aa
- branches of abdominal aorta
- into spermatic cord
blood supply: pelvic v drains into
pelvic veins drain into int iliac v
blood supply: R testicular v drains into
IVC
blood supply: L testicular v drains into
L renal v
nerve supply: sympathetic fibres from
- from spinal preganglionic fibres of T12- L2
nerve supply: sympathetic fibres function
- contraction of int anal sphincter, int urethral sphincter
- smooth mm contraction of reproductive tract
- facilitate movement of secretions during ejaculation
- innervate blood vessels
nerve supply: parasympathetic originate from
- S2-S4
nerve supply: parasympathetic fibres contribute to
- vasodilation
- bladder contraction
- erection
- modulate enteric plexuses distal to L colic flexure
