histology Flashcards
parts of male repro system
testes
conducting tubules/ducts
accessory glands
penis
testes
produce male germ cells and male hormone
conducting tubules/ducts
seminiferous tubule
epididymis
ductus deferens
urethra
accessory glands
produce and store seminal secretions
semen=sperm +secretions
role in ejaculation
exocrine fnx of testes
gametes
cytogentic gland-> produces cells
endocrine fnx of testes
androgens
tunica albuginea
thick fibroelastic CT
along posterior border of testis thickens and projects inward to create incomplete lobules
mediastinum of testes
hilum of testes
entry and exit of vessels, lymp, nn, ducts
lobule of testes
contains 1-4 coiled seminiferous tubules
embedded in loose CT stroma
leydig cells
single or clustered in stroma btwn seminiferous tubules
large irregular polyhedral interstitial cells
rounded nuclei w/1-2 nucleoli
many cytoplasmic inclusions
produce T therefore close to vessels
characteristics of leydig cells
prominent golgi abundant mito many peroxisomes extensive sER many peroxisomes lysosomes present
seminiferous tubules
site of:
spermatogenesis- spermatogonia transformed into spermatozoa
spermiogenesis- spermatids intospermatozoa
convoluted arching loops of seminferous tubules
may connect tubules w/in or btwn lobules
at termination convoluted tubule becomes straight tubule empties into rete tesis of mediastinum testis
histo of seminiferous tubules
heavy BM
collagen fibers ensheath tubule
peritubular contractile cells
spermatogenic epi- specialized stratified epi 4-8 cells thick
sertoli cells
scattered amongst germ cells in spermatogenic epi
provide developing germ cell w/mechanical support, protection, nutrition
sertoli cells histo
reach from BM to lumen
tall columnar cells
large pale oval nuclei w/prominent nucleolus and membrane infoldings
cytoplasm indented by developing germ cells
create blood-testes barrier
blood tested barrier
created by sertoli cells
seperates speratocytes from spermatogonia
spermatogenesis
occurs in coiled seminiferous tubules divided into 3 phases: -spermatocytogenesis -meiosis -spermiogenesis
spermatocytogenesis
speratogonis proliferate by mitotic division
type A -> type B -> spermatocyte
meiosis
primary spermatocyte -> secondary spermatocyte -> spermatid
2 divisions makes then 1N
spermiogenesis
spermatids -> spermatozoa
spermatogonia
cells sit on BM and are 2N
only germ cells present prior to puberty
type A spermatogonia
one daughter remains as type A
other becomes type B
type B spermatogonia
forms 2 primary spermatocytes
primary speratocytes
largest of sperm cells
meiosis 1 produces 2 secondary spermatocytes reducing chrom to 23
secondary spermatocytes
smaller then primary
meiosis 2 produces 2 spermatids-> 1N
spermatids
embedded in sertoli cells close to lumen
1N w/23 chroms
undergo speriogenesis
head of mature sperm
condensed nucleus and cap
dense acrosome contains hyaluronidase
neck and middle piece of sperm
contains core of longitudinal filiments
surrounded by mitochondrial sheath
powers mvmt of tail
tail of sperm
ensheathed by thin layer of cytoplasm
similar to cilium (9+2 MT arrangement)
tip is naked
cycle of seminiferous epi
humans 6 stages
segment- lenght of tubule varies
wave- distance btwn 2 similar stages
tubuli recti
straight seminiferous tubules
begins at apex of lobule
lining becomes simple columnar epi
tubule opens into rete testis
rete testis
irregular network of anastomosing channels in mediastinum of testis
efferent ductules
10-15 drain into ductus epidiymis
epididymis
formed by efferent ductules and ductules epididymis
ductus epididymis
single coiled duct 4-5m long
tall pseudostratisfied columnar epi w/sterocilia
continuous w/ductus deferens
ductus deferens
thick walled muscular tube
epi like ductus epeidiymis -tall pseudostratisfied columnar epi w/sterocilia
runs via inguinal canal in spermatic cord
courses retroperitoneally inot pelvis
terminally dialtes as ampulla
ends as ejaculatory duct
ejaculatory duct
formed by union of ampulla and seminal vesicles
empties into prostatic urethra
seminal vesicles
divertiula of ducti deferens postero-inferior surface of bladder irregular lumen and many folds/recesses epi depends on T produce and store mucoid secretions does NOT store sperm produces bulk of ejaculate fluid high in fructose
prostate gland
located inf to bladder, surrounds urethra
aggregate fo 30=50 tubulo-alveolar glands
divided into 3 zones:
peripheral (carcinomas)
transitional
central (BPH)
periurethral
prostate epi
glandular epi is hormonal dependent
glands develop in puberty
urethraprostatic concretions
aka corpora amylacea
enlargements that may constrict/block urethra
size and number increase w/age
prostatic secretions
make large portion of ejaculate
thin milky slightly alkaline fluid
contains acid phosphatase (used to diagnose prostatic epithelial malignany)
cowpers gland
bulbourethral glands pea sized compoud tubo-aveolar gland in mm of UGD ducts open into penile urethra secrete clear viscous mucoid substance occurs under erotic stimulation lumbricates urethra
corpous spongiosum
cylindrical body of vascular lacunae enclosed in CT capsule connected to venous plexus mucosal glands erectile function of glans penis
corpora cavernosa
2 dorsally
partially covered by sub-cutaneous tissue and thin skin
lack fat and hair follicles
terminally skin reduplicates as prepuce
epi over glans penis
stratisfied squamous, non-keritinizing
continuous w/urethral epi
flaccid
smooth m coils helicine aa shunts blood thry arterivenous shunts
erection
parasympathetic input straightens helicine aa, closes shunts, blood fills corporal caviites
tunica albuginea prevents over filling
ejaculation
-bulbourethral glands secrete mucus to lubricate urethra
-prostate gland discharge initiates true ejaculation
secretion neutralizes acidity of urine-bathed urethra
-sperm forced into urethra by m wall of ductus deferens
-seminal vesicle adds secretion pushing sperm and clearing urethra, rich in fructose
-bulbocavernosus m forces semen outside by compressing bulb of corpus spongisum
