Chapter 27: semen Flashcards
What is semen?
it is the fluid expelled during orgasm. (seminal fluid)
Whats the output of a typical ejaculation?
it contains 2 to 5 mL of semen, composed of about 2% to 5% of sperm and spermatic duct secretions, 25-30% prostatic fluid, 65%-70% seminal vesicle fluid, and a trace of bulbourethral fluid.
Whats the typical sperm count in semen?
it is 50 to 120 million sperm/mL.
What is considered infertility?
a sperm count any lower than 20 to 25 million sperm/mL.
What is semenogelin?
when its a sticky fibrinlike protein that promotes fertilization. The semenogelin entangles sperm, sticks to the walls of the inner vagina and cervix.
What is serine protease?
its a part of the prostatic fluid that breaks down semenogelin and liquifies semen. It is also known as prostate specific antigen (PSA).
What could and elevated blood PSA level indicate?
prostate cancer
What are the two most significant nutrients in semen?
fructose and citrate. They are metabolized by the sperm mitochondria to generate ATP for flagellar motility.
flagellar = the tail of the sperm
What is calcium needed for?
for flagellar beating, and it also plays an additional role in releasing enzymes fro mthe acrosome when the sperm penetrates an egg.
What does zinc do in the semen?
it stabilizes the chromatin in the sperm head; a dietary deficiency in zin can result in fragile sperm and infertility.
What helps limit the female immune response to sperm entering the vagina?
prostaglandins from the seminal vesicles.
