scrotum & penis of bull
pendulous scrotum & fibroelastic penis
scrotum & penis of stallion
ventral scrotum & vascular penis
scrotum & penis of boar
ventral scrotum & fibroelastic penis (corkscrew glans penis)
scrotum & penis of dog
ventral scrotum against body, bulbus glandis, os penis
scrotum & penis of cat
scrotum slightly ventral to anus, penis ventral to scrotum, penile spines
products of testes
fertile spermatozoa
spermatogenesis
production of sperm
spermatic cord houses...
ductus deferens, cremaster muscle & pampiniform plexus
function of spermatic cord
provide vascular, lymphatic & neural connection to body, provide a heat exchanger, & house the cremaster muscle
most mammals testes must be _____ than body temperature
4-6C cooler
ductus deferens in spermatic cord function
sperm transport
pampiniform plexus (PP) in spermatic cord function
temperature regulation
PP testicular artery
coiled network around ventromedial testis
PP testicular vein
surrounds testicular artery
cool blood to testis in spermatic cord
maintains testis temp less than body temperature & proper temperature for spermatogenesis
testosterone transfer in spermatic cord
high venous testosterone transferred to low arterial testosterone & elevated testosterone required for spermatogenesis
cremaster muscle
striated muscle that partially surrounds spermatic cord, attaches to parietal vaginal tunic, & facilitates blood flow to testes by relaxing & contracting
functions of scrotum
protection, support & temperature regulation
layers of scrotum
scrotal skin
tunica dartos
scrotal fascia
parietal vaginal tunic (scrotum)
viceral vaginal tunic (testis)
the skin of the scrotum
thick layer that decrease fat & hair
scrotum has sweat glands to...
allow evaporative heat transfer or cooling
scrotum has sympathetic nerves to...
activate thermo-receptors to increase panting for cooling
chronic & elevated temperature in testes in ____
detrimental
tunica dartos layer in scrotum
smooth muscle involved in temperature regulation
in tunica dartos, changes in scortal location relative to ___
body
contractions (cold), relaxation (hot)
changes in scrotal surface are: contracts ___ & relax ___
decrease & increase
scrotal fascia layer in scrotum
support
parietal vaginal tunic layer in scrotum
prevents adhensions which leads to free floating testes
testes function
spermatogenesis & endocrine
testicular capsule of the testes
covering of testis
visceral vaginal tunic of the testes
outer layer of testis proper
tunica albuginea of the testes
connective tissue layer under vaginal layer
functions of tunica albuginea
septal projections join mediastinum & contractions move sperm from rete tubules to mediastinum to efferent ducts
parenchyma of the testes
the functional tissue, 60-70% of cellular mass
seminiferous tubules
part of parenchyma, spermatogenesis location
seminiferous epithelium
where sperm cells are made
seminiferous epithelium compartments
adluminal, basal & interstitial
sertoli cells
in the adluminal compartment, somatic nurse cells for sperm, bind FSH & testosterone
junctional complexes
in the adluminal compartment, attach adjacent sertoli cells, it separates adluminal from basal compartment
germ cells in basal & adluminal compartment
basal : spermatogonium (diploid)
adluminal: spermatocytes, spermatids (haploid)
peritubular cells
surround seminiferous tubules
forms blood testis barrier with sertoli cells
prevent immunological destruction of germ cells
contractions move sperm & fluid to rete tubules
basement membrane of seminiferous tubules
separate basal from interstitial
leydig cells
in interstitial compartment, produce testosterone
functions of testosterone
stimulate secondary sex characteristics, increase muscle development promote accessory sex gland development (seminal fluid) & maintains libido & reproductive tract form or function
rete tubules in seminiferous tubules
drain the seminiferous tubules
mediastinum in seminiferous tubules
connects rete tubules to efferent ducts
function of efferent ducts
move sperm & fluid from the rete tubules to epididymus (head)
parts of the epididymus
head
body
tail
head of epididymus name
caput
proximal of caput of epididymus
rete fluid absorption
distal of caput of epididymus
secrets fluid
the sperm of caput of epididymus
no motility or fertility, proximal cytoplasmic droplet, fewest sperm
body of epididymus name
corpus
body of epididymus
maturation & concentrates sperm, fluid secretions
sperm in body of epididymus
some fertility & motility expression, can bind to oocyte translocation of cytoplasmic droplet
DNA in body of epididymus
increase disulfide cross linking
tail of epididymus name
cauda
tail of epididymus
storage (only distal tail sperm ejaculated)
sperm in tail of epididymus
normal fertility & motility, binds to oocyte (capacitation)
what happens to distal droplet in cauda epididymus
lost in tail, no loss indicates faulty maturation
the concentration on cauda epididymus
very high
function of epididymus
transport, maturation & storage
the transit time from head to tail....
is not affected by sexual stimulation
prolonged lack sexual stimulation cause what?
increased stale sperm which decrease fertility when ejaculated
ductus deferens
part of excurrent duct system, increase smooth muscle that transports sperms via muscle contractions from tail to ampulla
ampulla
part of excurrent duct system, enlargement of ductus deferens with enlarged mucosa, has some sperm storage
what are the accessory sex glands?
vesicular glands, bulbourethral glands & prostate
vesicular glands
paired glands that secret fluid into pelvic urethra, do not store sperm
what species have vesicular glands
bull, boar, stallion
what are the two types of prostate?
corpus prostate
disseminate prostate
what species have corpus prostate
bull, boar, stallion, cat, dog
what species have disseminate prostate
bull, boar, ram
dog have only what gland?
corpus prostate
corpus prostate
secretion cleans & lubricates urethra
bulbourethral glands
secretes alkaline fluid
what species have bulbourethral glands
ram, bull, stallion, boar, cat
function of seminal plasma
transport media (sperm + seminal fluid = semen)
culture media (provides environment for sperm viability)
stimulates sperm motility
retards sperm capacitation
stimulates sperm transport in female (oxytocin & PGF2alpha in seminal fluid increases myometrial
energy source of seminal plasma
fructose, fatty acids & amino acids
buffers of seminal plasma
control rapid pH changes
amino acids of seminal plasma
protect sperm membranes
glycoprotein of seminal plasma
prevents immediate activation of sperm
enzymes & ion of seminal plasma
increase sperm metabolism
accessory gland development is ___ on testosterone
dependent
function of penis
copulatory organ, duct for urine
ischiocavernosus muscle in penis
connects penis to ischial arch, contracts crus (hold blood inside penis)
bulbospongiousus muscle in penis
overlaps penis root, contracts, empties extra-pelvic urethra during ejaculation
fibroelastic penis
non-expandable with dense connective tissue
vascular penis
expandable with minimal connective tissue
glans penis
highly innervated, homologue to clitoris
what initiates ejaculation in glans penis
temperature & pressure
Spermatic Cord
...
Ductus Deferens
...
Ampulla
...
Vesicular gland
...
Bulbourethral gland
...
Scrotum
...
Testis
...
Retractor Penile Muscle
...