Lecture 2 (Male Reproductive System) Flashcards
Embryological start
1st trimester
Embryonic yolk sac produces germ cells
Travel up umbilical cord, go to tissues to form testes in the abdomen
Descent of Testes
Start high in the abdomen
But descend because it is too warm through the inguinal cancal and into the cooler scrotum, dragging duct and blood vessels
This happens within the 1st year after birth up until 2 years
Undescended testes
remain in the abdomen
Incr risk of sterility and incr risk of testicular cancer related to high temperatures
Testical
1 billion sperm in life time Surronded by the scrotum Epidydmis in the back Bigger than women's ovary Male menopause = decrease in sperm count
Seminiferous Tubules
3 Coiled tubules inside the testes where sperm is made 20 feet long
Interstitial cells of leydig
Produce testosterone
Undescended testical still make testosterone
Spermatogonia cells
Rest on a basement membrane
Do nothing until puberty
Spermatocytes -> primary then secondary spermatocytes -> spermatids -> embed in sertoli cells
Travels down the seminiferous tubles to epidydmis for storage and completes spermatogenesis
Spermatogenesis
Takes 64 - 72 days
Close to timing of ova devo if the ovaries alternate during the cyctles
Acrosomel cap
Tip of the sperm
Enzymes needed to get through the egg
Flagella
Tail of the spermatozoa
Ductus (Vas) deferns
Thought to orginally be an artery from the testes
Just carries sperm from the epididymis
Vasetomy
Back of the scrotom is opened
Ductus deferens is tied off in two places and then snipped on both sides,
1% decline in volume of ejaculates
99% is semen
Testicular Arteries
Carried as the testes descend making these arteries very long
Start around the renal area only in males
left testicle is lower than the right
Semen
Helps nourish sperm in the female reproductive system (a little acidic)
Produced in two spots
Seminal vesicles and prostate gland
Semial Vesicles
Semen
High in fructose,
Help sperm live, up to 5 days
Prostate Gland
Semen
No fructose, very alkaline pH
Sometimes vagina = acidic (Protects against infection)
Lowers the pH
Prostate Specific Antigen
Specific protein
PSA level was high = cancer
Really PSA high level = big prostate
Is found in breast milk
Benign Prostatic Hyperplasia (BPH)
increase sizeof prostae, product of aging
80% of men over 80 yrs have it = normal
May be caused by lower lvls of testosterone
Prostate Cancer
50% of men over 50yrs have prostate cancer, Frequently never leaves
Risk of removal may damage to nerves risk to erection and ejaculation
Bulbourethral glands
Produces precum before ejacultion
Will flush out penile urethra
Flush out acidic urine
Lubrication to the head of the penis
Reverse Ejaculation
If urethra is closed off during ejaculation, sperm in the urinary bladder
Pampiniform plexus of veins
cools arterial blood
Erection
Arterial blood fills the corpus cavernosa
Testicular Cancer Problems
Agressive cancer that will enter veins and lymphatics and travel throughout the body,
Killer of young men
