Male Mammalian Repro Flashcards
Explain how the male repro system develops
testis determining factor (TDF) produces testes develop which then turns into seroli cells secrete anti-mullerian hormone (AMH) which then causes AMH causes leydig cells to differentiate which can either turn into testosterone or dihydrotestosterone. Testosterone will develop into male duct system. Dihydrotestosterone will develop penis, scrotum and accessory sex glands.
explain how sperm is made in testes and exists the penis
explain the 2 main jobs of male gonad
produce hormones
produce sperm
true/false
the testis rest outside of the abdominal cavity
true
what is the temp of the testis for proper spermatogenesis
33 degree Celsius
what are the 4 jobs of the scrotal skin (protect, contains what two things and what is it necessary for)
1) protects and supports the testis
2) contains temp sensitive neurons
3)contains sweat gland
4) necessary for spermatogenesis
where is the tunica dartos located
muscle layer lining the scrotal skin
what is the main job of the tunica dartos and how does it do it
its temp dependent and temp sensitive which means that it relaxes during high temp to increase surface area and heat dissipation and then contracts during cool temp to decrease surface area and heat dissipation
where is tunica dartos located
muscle layer lining the scrotal skin necessary for spermatogenesis
where is tunica albuginea located
dense white connective tissue covering the testis
where are leydig cells located
between the seminiferous tubules
what are leydig cells the site of
testosterone production
what are leydig cells surrounded by
lymphatic tissue and blood vessles
what do sertoli cells line
line the inside of the seminiferous tubules
what do sertoli cells serve as
site of sperm cell production
what does sertoli cells contain
contain immature sperm cells at various stages of development
what do rete tubules connect
connect seminiferous tubules to the efferent ducts
what do the rete tubules transport
spermatozoa and secreted fluids
what does mediastinum cover
the rete tubules
what does the mediastinum provide
structural support and gives the testis an oblong shape
what is the connective tissue core of the testis
mediastinum
what do efferent ducts do
connect the rete tubules to the head of the epididymis
what does the efferent ducts lined with
lined with ciliated and non ciliated absorptive columnar cells which are surrounded by smooth muscle
where is the head of the epididymis located
located dorsal to the testis
where is the body of the epididymis located
along side the testis
where is the tail of the epididymis located
located ventral to the testis
what are the 4 functions of the epididymis
1) passage way for sperm cells from the efferent ducts to the vas deferens
2) sperm cell maturation
3) absorption of fluids to increase sperm cell concentration
4)storage of sperm cells (primarily in the tail)
how long do sperm cells remain in the epididymis for
2 weeks
what does the spermatic cord provide for the testis
support it maintains connection between testis and internal portions of the male repro tract following testicular descent
what is cryptorchidism
unilateral and bilateral
unilateral- 1 testis remains in the abdominal cavity and 1 descends into the scrotum
bilateral- 2 testis remain in the abdominal cavity (sterile)
what is a scrotal hernia
viscera enter the scrotum
what does the spermatic cord support (3)
vas deferens
cremaster muscle
pampiniform plexus
what does vas deferens connect
connects tail of the epididymis to the urethra
what does the cremaster muscle aid in
aid in support and protection of the testis
what is the cremaster muscle dependent on
testosterone
how is the cremaster muscle temp sensitive
relaxes during high temp to move further from body
contracts during cool temp to bring testis closer to body
what is the pampiniform plexus
it has veins and arteries that supplies blood to the testis
counter current heat exchange system
necessary for spermatogenesis
how does the pampiniform plexus counter current heat work
cool venous blood (33 degree Celsius) decreases temp of the warm arterial blood (39 degrees Celsius)
what are the 4 distinct mechanisms that testicular temp is maintained at 33 degree Celsius
1) thermosensitive neurons (in scrotal skin which regulate sweat glands and regulate respiratory center)
2) tunica dartos muscle (contracts/relaxes)
3) cremaster muscle
(contracts/relaxes)
4) pampiniform plexus (warm arterial blood is cooled by venous blood
what are the 4 factors that disrupt spermatogenesis
1) high temp
2) febrile diseases for 3-5 days
3) transporting animals
4) showing of the animal
where is the anatomical location of the accessory sex gland
after the vas deferns
what are the 4 things that accessory sex glands provide
1) suspending medium for sperm transport
2) nutrients (fructose)
3) buffers
4) species variation in size and function
what are the 4 parts of the accessory sex glands
1) ampulla
2) seminal vesicles
3) prostate
4) bulbourethral gland or Cowpers gland
what does ampulla serve as
point where two vas deferens join
what does seminal vesicle do
provide 40-80% of ejaculate volume
main contributor of fructose in ejaculate
what does prostate do
provide 15-30% of ejaculate volume
contribute citric acid as an energy source
what does bulborurethral gland or cowpers gland do
provide 15-25% of ejaculate volume
provide alkaline materials and buffers to neutralize pH of the urethra
what animals have a fibroelastic type of penis
bull
ram
boar
explain fibroelastic type of penis
rigid in non erect state
only a small amount of blood enters the penis and slightly enlarges it at erection
what is fibroelastic type of penis supported by and how does it work
mainly supported by the sigmoid flexure and retractor penis muscle
during erection the sigmoid flexure straightens and the retractor penis muscle relaxes
what animals have a vascular type of penis
stallions and primates
explain the vascular type of penis
no sigmoid flexure, erection is achieved by engorgement of the penis with blood
what animal has the baculum and bulbus glandis type of penis
dogs
explain baculum and bulbus glandis type of penis
erection is achieved by engorgement of the penis with blood
penile bone (baculum)
understand the anatomy of this picture where everything is located
