Repro Session 4 Flashcards
4 component parts of male reproductive system?
paired testes- site of spermatozoa production, and sex hormone secretion
duct system- transports spermatozoa to urethra
accessory sex glands- supply fluid components to semen: prostate, seminal vesicles, bulbourethral glands
penis
type of gland the testis is?
compound tubular gland
What does the tunica albuginea form posteriorly that contains many interconnected channels which provide passageways for sperm to enter duct system?
mediastinum testis
muscle contained within superficial fascia of the scrotum?
dartos muscle
what are the testes contained within?
the scrotal sac
the 2 types of cells found within the seminiferous epithelium?
sertoli cells (supporting cells) spermatogenic cells (germ cells)
most primitive spermatogenic cells?
spermatogonia-rest on BM
distinguishing between spermatids and spermatozoa on microscopy?
spermatids- lightly stained round nucleus
spermatozoa- deeply staining heads, which appear to be embedded in sertoli cells, their tails hanging into lumen of seminiferous tubule
approximate length of spermatogenesis?
70 days
what is oligozoospermia?
clinical condition where abnormally low number of spermatozoa in semen.
what is azoospermia?
no sperms appear in ejaculate
what is cryptorchid (maldescended) testis, and what problems can it create?
spermatogenesis impaired as elevated temperature. Germs cells absent, while Sertoli and Leydig cells secrete male sex hormones.
Associated with increased incidence of malignant testicular tumours
what is orchitis?
inflammation of testes- occurs in some people who suffer mumps after puberty, causing impaired spermatogenesis, occasionally leading to seminiferous tubule degeneration, or at times, infertility.
what happens to sperm in the epididymis?
transport, mature, stored
stored in tail segment until ejaculation
name of terminal portion of vas deferens?
ampulla
how is the ejaculatory duct formed?
ampulla of vas deferens joins with duct of seminal vesicle
ejaculatory duct then opens into prostatic urethra
epithelial lining of ductus epididymis- duct of the epididymis?
pseudostratified columnar with stereocilia
discontinuous layer of longitudinally-oriented strands of striated muscle enclosing spermatic cord?
cremaster muscle
collection of small veins surrounding vas deferens, and forming most bulk part of spermatic cord?
pampiniform plexus
which bacteria may cause epididymitis?
N gonorroheae, E coli, Chlamydia trachomatis
sequence of secretions that forms ejaculate?
bulbourethral glands
prostate
spermatozoa
seminal vesicles
where do the seminal vesicles lie?
posterior to prostate
where are the bulbourethral glands located?
within the urogenital diaphragm
3 cylindrical bodies of erectile tissue forming the penis?
2 corpora cavernosa penis
single corpus cavernosum urethrae (corpus spongiosum)
importance for testes to be contained within scrotum?
keeps them at the low temperature necessary for spermatogenesis by allowing the testis to sit outside of the body
what remnant of peritoneum forms a fluid filled structure around testes?*
tunica vaginalis
why is the spermatic cord important to the testes?
it contains the testicular blood vessels- testicular artery and pampiniform venous plexus, and the ductus deferens
function of the small amount of fluid in the cavity of the tunica vaginalis?
to allow testes to move freely in scrotum
origin of testicular arteries?
abdominal aorta, just inferior to renal arteries- IV disc between L1 and L2 vertebrae
origin of testicular veins?
pampiniform venous plexus, which lies anterior to the vas deferens and surrounds the testicular artery in the spermatic cord
drainage of testicular veins?
R: IVC
L: left renal vein
drainage of testicular veins?
R: IVC
L: left renal vein
how may the cremasteric reflex be evoked and what does it demonstrate?
by lightly stroking medial aspect of superior part of the thigh, which causes the cremaster muscle to contract and result in rapid elevation of the testis on the same side. Area of skin supplied by ilioinguinal nerve which synapses in the SC and activates the motor fibres of the genital branch of the genitofemoral nerve causing cremaster muscle contraction
problem of hyperactive cremasteric reflex in children?
may be mis-diagnosed as cryptorchidism
hyperactive reflex can be aboloished by getting children to sit cross-legged in a squatting position as if the testes are descended, they can then be palpated in the scrotum
problem of hyperactive cremasteric reflex in children?
may be mis-diagnosed as cryptorchidism
hyperactive reflex can be aboloished by getting children to sit cross-legged in a squatting position as if the testes are descended, they can then be palpated in the scrotum
where is the internal spermatic fascia derived from?
transversalis fascia
where is the cremasteric spermatic fascia derived from?
fascia of both superficial and deep surfaces of internal oblique muscle, and transversalis fascia
where is the external spermatic fascia derived from?
external oblique aponeurosis and its investing fascia
describe the course of the spermatic cord
begins at deep inguinal ring, lateral to the inferior epigastric vessels, passes through inguinal canal, exits at superficial inguinal ring, and ends in the scrotum at the posterior border of the testis
why is a L sided varciocele more common than a R sided one?
because the acute angle of entry of the R testicular vein into the IVC is more favourable to flow than the nearly 90 degree angle at which the L testicular vein enters the L renal vein, making it more susceptible to obstruction or flow reversal
contents of the scrotum?
testis
first part of spermatic cord
epididymis
optimum temp for enzymes responsible for spermatogenesis?
2 degrees below normal body temp
what is the septum of the scrotum?
continuation of dartos fascia separating scrotum into R and L compartments internally, 1 for each testis
how is septum of scrotum marked externally?
by scrotal raphe- cutaneous ridge marking line of fusion of labioscrotal swellings
what is the internal spermatic fascia lined by internally?
the parietal layer of the tunica vaginalis
what is the sinus of the epididymis?
slit-like recess of tunica vaginalis, between body of the epididymis and PL surface of testis
where does an undescended testis commonly lie?
in the inguinal canal
why is increased risk of testicular malignancy in undescended testis in cryptorchidism part. problematic?
not palpable and not usually detected until cancer has progressed
what structures enable an adequate temp in testes for spermatogenesis to occur?
dartos muscle
cremaster muscle
pampiniform venous plexus
location of scrotum in relation to penis and pubic symphysis?
PI to penis, and inferior to PS
where is the surface of the testis not covered by the visceral layer of the tunica vaginalis?
where testis attaches to epididymis and spermatic cord
what is the processus vaginalis and how is it formed formed?
peritoneal invagination which made pathway for descent of testes into scrotum
musculo-fascial layer evaginates into scrotum as it develops, together with peritoneal membrane