Male Repro Flashcards
male reproductive tract consists of 8 things
testes epididymus vas deferens seminal vesicles prostate bulbourthral ejaculatory duct penis
what is the function of the testes?
produce gametes (sperm)
what is the function of the epididymis?
sperm transport and site of sperm maturation
what is the function of the vas deferens
sperm transport and storage
what is the function of the seminal vesicles, prostate and bulbourethral glands
produce nutrients and buffers
what is the function of the ejaculatory duct?
transport of sperm and fluids
what is the function of the penis
delivery of sperm into female repro tract
what 5 major hormones are involved?
LH, FSH, testosterone, GnRH and inhibin
spermatogenesis is the development of the
male gametes from the spermatogonia to the spermatozoan stage
when does spermatogensis occur?
starting with puberty
the sertoli cells do what for developing sperm?
they surround and nurture it
sertoli cells also secrete
growth factors
the growth factors that sertoli cells secrete seem to regulate 3 things
- mitosis
- meiosis
- development of the spermatozoa
the sertoli cells form a_______ barrier
the sertoli cells form a blood-testis barrier
sertoli cells secrete fluid within the lumen of the ___________
seminiferous tubules
sertoli cells secrete androgen binding protein which does what?
keeps concentrations of androgens very high in tubules and ducts
the seminal vesicles, bulbourethral and prostate secrete what?
components of the semen
major function of the Leydig cells is to
synthesize and secrete testosterone
what hormone is necessary for Leydig cells to function?
LH
what are the 2 crucial steps to testosterone synthesis
- conversion of cholesterol to pregnenolone
2. cleavage of the side chain at C17
what are the 2 major androgens?
- testosterone
2. dihydrotestosterone
testosterone can be metabolized peripherally to what?
estradiol
what enzyme converts testosterone to estradiol?
aromatase
where is aromatase primarily found?
in the brain, breast and adipose tissue
what convertes testosterone to dihydrotestosterone?
5-alpha reductase
where is 5-alpha reductase found?
skin & scalp
genital skin, prostate
where is testosterone primarily degraded?
by the liver
androgens promote what 3 things to organs of repro?
growth, differentiation and function
androgens are necessary for what function involving sperm?
spermatogenesis
androgens stimulate the growth of
chest, axillary and facial hair + male pattern baldness
androgens increase
libido
testosterone is responsible for the development of what 5 things?
wolffian duct structures formation of male internal genitalia spermatogenesis increased muscle mass increased libido
DHT is needed for the development of what 5 things?
male external genitalia enlargemnt of prostate/penis facial hair acne recession of hairline
testosterone and DHT are what type of hormone?
steroid
testosterone and DHT work by binding at
intracellular receptors
LH, FSH and testosterone are required for
testicular function
LH acts on ______ to stimulate testostereon ____ & secretion
LH acts on Leydig to stimulate testosterone production & secretion
testosterone works with ____ to stimulate the _____ cells
FSH, sertoli
LH and FSH are released from what gland?
pituitary
what stimulates the release of LH and FSH?
GnRH
what is the GnRH pulse????
it’s produced in the hypothalamus and released into the portal circulation with a frequency of once an hour to once every 3 hours
Testosterone inhibits ____ secretion
GnRH
when GnRH is inhibited it inhibits what hormoen from the pituitary?
LH
sertoli cell produce a hormone that inhibits what?
inhibin, FSH
