Male Reproductive Physiology Flashcards
The pulsatile secretion of what hormone initiates puberty?
GnRH
GnRH drives the pulsatile secretion of what hormones? What are these hormones responsible for?
FSH and LH -secondary sex characteristics
During the adult reproductive period, is LH or FSH secreted more?
LH
What is the function of the testes?
1) Spermatogenesis 2) Testosterone secretion
What is the function of the epididymis?
Primary location for maturation and storage of sperm
What is the function of the vas deferens?
-Storage for sperm -Secrete rich fluid
What is the function of the sminal vesicle?
Secretes fluid that aids in the motility of sperm and penetration –> becomes semen -prostaglandins helps semen react with female cervix -helps ejaculated sperm into fallopian tube and uterus
What is the function of the prostate gland?
Secrete solution that gives the semen an alkaline pH to survive in the acidity in female vagina
What two type of cells are found in the seminiferous tubules? What are their functions?
Sertoli cells: produce sperm and forms barrier between testes and bloodstream Leydig cells: produce testosterone
Where are spermatogonia and spermatozoa found?
Spermatogonia (immature sperm): periphery Spermatozoa (mature sperm): lumen of tubule
What are the androgens secreted by testes
Testosterone (most abundant)
Dihyrotestosterone (DHT)
Androstenedione
What cells synthesize and secrete Testosterone
Leydig Cells
In the lumen of the seminiferous tubules, how is testosterone concentrated?
Testosterone is bound to androgen-binding protein (ABP) -ABP secreted by sertoli cells
What converts androstenedione to testosterone?
17β-hydroxysteroid dehydrogenase
What is the active form of testosterone in some tissue
Dihydrotestosterone (DHT)
What converts testosterone to dihydrotestosterone (DHT)?
5α-reductase
In circulation, what is testosterone bound to?
Sex hormone binding globulin (SHBG)
What is the first step in testosterone production?
Cholesterol –> Pregnenolone -RATE LIMITING STEP