[PHYSIO] MALE REPRODUCTIVE SYSTEM Flashcards
function of male reproductive system
spermatogenesis
sperm delivery to female
primary reproductive organs
testes
secondary reproductive organs (9)
1-bulbourethral glands
2-prostate
3-seminal vesicles
4-epididymis
5-vas deferens
6-ejaculatory duct
7-urethra
8-penis
9-scrotum
1st step of spermatogenesis supported by
GH
steps 1-4 of spermatogenesis supported by
testosterone
4th step of spermatogenesis supported by
Estrogen
FSH
80% of testes is formed of
seminiferous tubules
spermatogenesis occurs in
seminiferous tubules
testosterone is secreted by
Leydig cells of testes
walls of seminiferous tubules are lined by
primitive germ cells
spermatogenesis supporting cells
Sertoli cells
spermatogenesis takes about
74 days
stages of spermatogenesis
Mitosis
Meiosis (I & II)
Spermiogenesis
spermiogenesis* definition
production of spermatozoa from spermatids by removal of cytosol & organelles not needed for fertilization
germinal epithelium development + maintenance stimulated by
testosterone
testosterone functions (3)
1-germinal epithelium development + maintenance
2- mitotic + meiotic divisions
3- acts on sertoli cells for spermatid maturation
LH function
(+) Leydig cells–> Testosterone secretion
FSH function
(+) Sertoli cells–>spermatid maturation + ABP production
GH function
early division of spermatogonia
absence of GH leads to (pituitary dwarfs)
Spermatogenesis deficient/absent–>infertility
prolactin function
(-) testosterone synthesis
spermiogenesis* helped by
testosterone
estrogen
FSH
hormones affecting spermatogenesis (6)
1-Testosterone
2-LH
3-FSH
4-Estrogen
5-GH
6-Prolactin
Estrogen function
spermiogenesis
estrogen in males is formed by
aromatization of testosterone in Sertoli cells
optimum temp for sperm
32-35 C
testes descend in
7th month of pregnancy
testes descent is under effect of
fetal testosterone
testes are kept cool by
1- outside abdominal cavity
2-circulating air in scrotum
3- No subcutaneous fat
4-countercurrent heat exchange b/w spermatic arteries & veins
blood-testis barries is formed by
SERTOLI CELLS
blood-testis barrier functions
1-prevents large molecules passage into seminiferous tubules
2-maintains fluid composition in tubular lumen
3-osmotic gradien= ↑fluid in tubular lumen
4-protects germ cells from blood-borne antigens
5-prevents antigenic byproducts of germ cell division from entering blood
composition of tubular fluid
↑ androgen, estrogen, K+, glutamic & aspartic acids
very little protein & glucose
Sertoli cells function
1-blood-testis barries formation
2-sperm nutrition
3- phagocytosis
4-fluid secretion to push sperm into epididymis
5-ABP secretion
6-Inhibin secretion
7- MIF secretion
8- Estrogen formation
ABP action
↑ testosterone conc in seminiferous tubules
Inhibin action
(-) FSH (by anterior pituitary)
MIF action
(-) Female internal genitalia formation by causing Mullerian duct regression
Phagocytic function of sertoli cells
1-phagocytose cytoplasm extruded from spermatids
2-destroy defective germ cells
A.Sperm energy source?
B. Sertoli cells provide nutrition for sperm through?
A. Lactate
B. ↑ glycogen concentrations
↳glucose conv to——> Lactate
Epididymis function
1-sperm storage
2-sperm concentration
3-sperm maturation & motility
4- CatSper channels formation
CatSper channels located in
sperm tail membrane
CatSper mechanism of action
alkaline sensitive
activated when sperm travels from acidic vagina to alkaline cervix–> ↑ Ca2+ entry which causes:
1. Capacitation
2. Hyperactive motility
3. Acrosomal reaction
vas deferens function
sperm storage for upto 2 months