Male Repro Flashcards
The “plumbing” of the Male reproduction system is responsible for what two reproductive processes?
1-transport of sperm
2-development of sperm seminal volume
Where are the proteolytic enzymes necessary to break down the zone pellucida of the egg stored?
Acrosome (causing acrosome reaction)
The cytoskeletal component of the sperm flagella, formed from microtubles is called what?
axoneme (can help the sperm reach a max velocity of 1-4 mm/min)
How does a sperm direct itself toward the egg?
following the progesterone gradient sensed via chemotactic sensors on the sperm
In which specific structure does spermatogenesis take place?
seminiferous tubules
Germinal cells that give rise to sperm are called what?
spermatogonia
The nursing cells that help form the blood-testis barrier are called what?
Sertoli cells
How long does spermatogenesis take?
64 days
Primary spermatocytes are ________ and become ________ starting with secondary spermatocytes
diploid, haploid
Inhibin does what?
negative feedback in excess FSH secretion, produced by sertoli cells
Estrogens are formed by converting testosterone to estrogen via what cells?
sertoli cells
How many mature sperm are produced per day by 2 human testicles and how long is it stored?
120 million/day. Can be stored for at least a month
What 3 things do seminal vesicles contribute to semen?
- Fructose
- Prostaglandins (thin cervical mucus and cause reverse peristalsis)
- Fibrinogen (clot is cleaved later)
*contributes 60-70% of volume
What 3 things are present in the thin fluid that the prostate contributes?
1-Clotting enzymes (cause semen to clot and keep in place)
2-Pro-fibrinolysin (plasminogen, breaks down the clot over time)
3-Various alkaloids (pH of 6.5 is optimal for sperm)
*contributes 25-30% final volume
Bulbourethral glands (cowpers gland) are responsible for what?
pre-ejaculate lubrication (1% final volume)
What is the final pH of semen?
around 7.5
What changes happen to the sperm upon entering the female environment?
- inhibitory cholesterol coating is washed away by female fluids
- cell membrane around acrosome becomes weak
- calcium permeability increases causing more vigorous motion
What division controls erection innervation?
parasympathetic in sacral spine (pre-ejaculate is also released because of parasympathetics)
Ach, nitric oxide and other vasoactive transmitters cause vasodilation and engorgement of what two regions?
- corpora cavernosa (lateral)
- corpus spongiosum (ventral)
What innervation division controls ejaculation?
sympathetic impulses causing vas deferens to contract and move toward seminal vesicles
What is the term for the steps leading up to ejactulation?
emission
What two muscles rhythmically contract causing ejaculation?
- ischiocavernosus
- bulbospongiosus
