Male anatomy Flashcards
Secondary sex organs…?
Duct system for transport (eg. epididymis, ductus deferens)
Primary sex organs…? What do they produce?
testes which produce male gametes (sperm) & testosterone
Accessory organs…?
Provide fluids (eg. prostate gland, ampullae, seminal vesicles, bulbourethral gland)
What are the basic components of the male reproductive tract?
spermatic cord, scrotum, testis, excurrent duct system, accessory sex glands, penis & muscles for erection, protrusion, emission & ejaculation
Draw the male reproductive tract
slide 4…amongst others
Characteristics of the spermatic cord…?
- Suspends testis through the inguinal canal
- provides pathways from body -> testis for vasculature, lymph & nerves
- houses: ductus deferens, cremaster muscles, pampiform plexus
Function of the ductus deferens?
transport sperm
Function(s) of the cremaster muscle?
- primary muscle for supporting testis
- aids in temp. control by pumping action of blood thru pampiform plexus
Function of pampiform plexus?
heat exchange via venous network
keeps testicular temp 4 to 6 degrees lower than body temp
counter current heat exchanger
- venous blood from testis cools arterial blood to testis
- requires venous blood cooling by direct heat loss thru skin of testis
Learn differences between bull, stallion, boar, dog, tom
slide 7-11
Outline the blood supply to the testes…Fill in blood supply on reproductive organs pictures
slide 12
Higher testis temps can cause…?
lower motility
reduced embryo survival in normal ewes mated to heat treated rams (DNA damage)
What are some other contributors towards thermoreg?
- cremaster muscle (striated muscle can cause short term elevation of testes) - functions to create pumping action -> pampiniform plexus -> enhance cooling
- sweat glands & thermosensitive nerves on the scrotal skin
- Tunica dartos (smooth muscle - sustained contractions to keep testes close to body for sustained periods during extreme cold temps)
When are scrotal sweating & thermal polypnea (panting) pathways activated?
When scrotal temperature reaches about 39 degree centigrade
Characteristics of the scrotum…?
- 2 lobed sac
- consists of: skin, tunica dartos, scrotal fascia, parietal vaginal tunic
- skin has many sweat glands for temp control, thermo sensitive nerves for regulating sweating & resp. rate
Characteristics of the testes…?
paired organs
produce spermatozoa, testosterone, fluid to suspend sperm to aid removal from testes
Testicular capsule contains…?
visceral vaginal tunic & tunica albuginea - help pump sperm around
Parenchyma contains…?
tubular compartment (seminiferous tubules) interstitium (Leydig cells, capillaries, lymph vessels, connective tissue)
Seminiferous tubules contain…?
seminiferous epithelium
Sertoli cells
developing germ cells
peritubular cells
Function of blood - testis barrier?
prevents immunologic destruction of developing germ cells
Blood testis barrier is formed by…?
peritubular cells (1st barrier) junctional complexes (tight junctions) between Sertoli Cells (2nd barrier)
Sertoli cell secretions…?
Androgen binding protein (ABP)
sulfated glycoproteins (SGP) 1 & 2
inhibin
transferrin
The excurrent duct system consists of…?
- Efferent ducts - sperm & fluid to the epididymis
- The epididymal duct - final maturation storage, heat (caput), body (corpus), tail (cauda)
- Ductus deferens - delivery of sperm to pelvic urethra
Accessory sex glands…?
Ampullae, seminal vesicles, prostate, bulbourethral gland are the accessory glands and along with epididymis serve to produce seminal plasma (liquid, noncellular portion of semen)
Bulbourethral gland is small in which animals?
bull
stallion
ram
Characteristics of the penis…?
copulatory organ
consists of: the base, shaft, glans penis
Boars, bulls & rams have what kind of penis’?
fibroelastic penises with limited erectile tissue
contain sigmoid flexure (allows retracting of penis within sheath) controlled by retractor penis muscles
NO INCREASE IN DIAMETER
A bit about the shaft…
spongy erectile tissue
corpus cavernosum
corpus spongiosum surrounds penile urethra
The penis of the stallion & dog…the similarities…
have musculo-cavernous penis
sigmoid flexure is absent
diameter of penis increases during erection
The unique aspects of the dog penis…?
2 distinct regions
Bulbus glandis - responsible for the copulatory lock (dog tie) during copulation
Pars longa glandis
Penis shape in a boar?
corkscrew shaped glans penis
Glans penis of tom cat has which structures?
spines that are androgen dependent
From scrotal skin to testis (layers)…
scrotal skin, tunica dartos, scrotal fascia, parietal vaginal tunic, vaginal cavity, visceral vaginal tunic, tunica albuginea
Events of erection…
blood pumped by IcM -> corpus cavernosum & corpus spongiosum -> elongation and straightening of sigmoid flexure -> penis protrudes from prepuce
Events of intromission…
entry of penis into vagina
Events of emission…
movement of ejaculate of along ductus deferens -> urethra -> mixed with secretions from accessory glands
Events of ejaculation…
Ejection of semen from the penis involving -> contraction of urethralis & bulbospongiosus muscle (sometimes free end of penis spirals)
Which species have urethral process’?
ram & stallion
