male urethra/ repro

the male urethra consists of what 4 parts

pre-prostatic

prostatic

membranous

spongy

prostatic urethra

inside the prostate, most dilated

ends where urethra is covered by external urethral sphincter

Prostatic urethra contains what on its posterior wall?

urethral crest on its posterior wall on both sides of which are the prostatic sinuses

into which most prostatic ductules open?

the prostatic sinuses

where do ejaculatory ducts open?

on or near the prostatic utricle

membranous urethra surrounded by?

external urethral sphincter nd perineal membrane

what is posterolateral to the membranous urethra?

Cowper’s glands; opens into spongy urethra

why is the membranous urethra most vulnerable to injuries?

due to being fixed and less mobile

spongy urethra

15-16 cm long

starts from bulb of penis nd ends at external urethral orifice of glans penis

what does the epididymis consist of?

head, body, and a tail

where is the epididymis located?

lies on the posterior surface of the testis, covered by tunica vaginalis except its posterior border

where is spermatozoa produced?

in the lumen of seminiferous ducts

ptway of spermatozoa?

seminiferous ducts

rete testis nd efferent ductules

epididymis (for maturation +storage)

vas deferens mucosa

has high columnar double layered epithelium w sterocilia

what does the vas deferens have before joining the duct of seminal vesicle?

dilation called ampulla of ductus deferens

the contractio, suction and pressure mechanism in vas deferens is assumed to do what?

play role in the quick passage os spermatozoa

where does the vas deferens ascend?

in the spermatic cord

seminal vesicle opens into where?

vas deferens, producing the ejaculatory ducts which enter the prostate

seminal vesicle(s) produce an alkaline secretion, which together with prostatic fluid constitute what?

the bulk of semen

seminal vesical location

lie posterior to the bladder btwn rectum nd fundus of the bladder, and superior to the prostate

largest accessory gland of male repro

prostate (3 cm long)

where is prostate located?

behind pubic symphysis

prostate shape and size?

like a chestnut

Is the prostate palpable?

yes, its palpable Infront of the rectum via rectal exam

what happens during emission?

sympathetic stimulation (L1+L2) causes vas deferens n seminal vesical to deliver semen from epididymis to prostatic urethra by peristalsis

what is ejaculation?

projectile outflow of semen from external urethral orifice

during ejaculation where does semen pass?

the internal urethral orifice

what happens after ejaculation?

penis becomes flaccid again and helicine arteries contract (symp. stim) which allow blood flow out

—refractory period

what happens to the muscles of the penis after ejaculation?

they relax

during an erection, what happens to the helicine arteries in corpora cavernosa?

helicine arteries relax due to stimulation of s2-s4 cavernous nerves from prostatic plexus (PARASYMP)

after step 1 of erection what happens?

blood fills sinuses of corp. cavernos; tunica albuginea become tightened

in step 3, what happens when bulbospongiosus nd ischiocavernosus muscles contract?

veins get compressed in corp. cavernosa, restricting blood flow

since blood flow gets restricted due to veins being compressed in corp. cavernosa, what happens in step 4 of erection?

as a result, both corp. cavernosa + spongiosum become enlarged, rigid and penis erects