Male Reproduction, Sperm, Tumescence and Climax Flashcards
What are the testicular appendix a remnant of?
Paramesonephric ducts (Mullerian)
What is the glandular capsule of the testis?
Tunica albuginea
Where do Leydig cells reside?
In the extracellular space
Structure of Sertoli cells?
Highly irregular with nucleolus always having two smaller satellite bodies
Sertoli cells function?
Forms the blood-testis barriers forming tight junctions; separate gametes from blood
What is the primary stimulating hormone for Sertoli cells?
FSH
What do Leydig cells do?
Produce testosterone in the presence of LH
Progression of sperm maturation?
Spermatogonium Primary spermatocyte Secondary spermatocyte Spermatid Spermatozoa
What stage of sperm are found in the basal compartment?
Spermatogonium
What stage of sperm are found in the adluminal compartment?
Sc1
Sc2
Spermatid
Spermatozoa
Where do Sertoli cells rest?
On the basement membrane
Why does only one sperm enter the oocyte?
Once sperm penetrates zona pellucida and fuses with oolemma the ovum releases granules into the perivitelline space preventing the binding of additional sperm and causes additional sperm to fall off, also the oocyte membrane because electrically depolarized fending off additional sperm
As the testis move from the abdomen to the scrotum they pick up layers and change names, what are the layers from deep to superficial?
Peritoneum-> tunica vaginalis
Transversalis fascia and aponeurosis-> internal spermatic fascia
Internal oblique abdominus muscle-> Cremaster muscle and fascia
External oblique abdominis aponeurosis-> External spermatic fascia
Superficial abdominal fascia (Camper’s fascia)-> Dartos muscle and fascia
Perineal skin-> Scrotum
What does the spermatic cord consist of?
Vas deferens
Several arteries
Nerves
Veins
What occurs vascularly for an erection to occur?
Blood rapidly enters the cavernous bodies causing swelling and pressure on the deep dorsal vein collapsing it
Ventral and dorsal side of the penis?
Ventral is the back of the penis
Dorsal is the front when flaccid
What controls blood flow to the penis?
Both PSNS and SNS
What relays sensory information from the back half of the scrotum and perineum?
Pudendal nerve
Bulbourethral gland function:
Lubrication
Prostate gland secretions contents:
Citrate
Calcium
Zinc
Acid phosphatase
Citrates function:
Major anion in seminal plasma (function not known)
Calcium function:
Important fro sperm swimming and acrosome reaction
Zinc function:
Enzyme action, binds many types of proteins
Acid phosphatase function:
Neutralizes acid pH of semen and vaginal/cervical secretion
Seminal vesicle secretion contents:
Fructose
Prostaglandin
Fructose function:
Energy for sperm swimming
Prostaglandin function:
Contraction of female reproductive tract
Spermatogenesis pathway:
Spermatogonia mitose to primary spermatocytes-> 1st meiotic division to secondary spermatocytes-> 2nd meiotic division to spermatid (only mature to spermatozoa)
What do Sertoli cells release in response to how many sperm are bound to its surface?
Inhibin
What is inhibin?
A negative feedback substance for FSH
What drives spermatogenesis and allows more spermatocytes to be bound to Sertoli cells?
FSH
What supplies the dorsum of the penis with innervation?
Genital nerves
What are two ways an erection can occur?
Physical stimulation directly sent from pudendal to brain
Sensory information to the mammillary bodies and efferent signals to penis
What nerves act when flaccid?
Sympathetic neural tone by releasing norepinephrine causing contraction and not allowing too much blood flow to the penis
What nerves act when erection occurs?
Parasympathetic by releasing Ach causing vasodilation
What is released causing tumescence?
NO
PGE1
Increased cGMP causing dilation
What roots are the PSNS nerves?
S2-S4
What occurs during ejaculation?
Sympathetic stimuli cause contraction of ischiocavernosal and bulbocavernosal muscle with peristaltic contractions of epididymides and all the ducts
Path of sperm in reproductive tract:
Seminiferous tubules Epididymis Vas deferens Ejaculatory duct (Nothing) Urethra Penis
Accessory glands in order they secrete fluid to contribute to semen:
Seminal vesicles
Prostate gland
Bulbourethral glands
