male reproductive system Flashcards
function?
to produce spermatocytes and male sex hormones.
Internal organs?
testis, epididymis, deferens duct, seminal vesicular and prostate.
External organs ?
scrotum, penis and urethra masculine.
describe testis. location ,function, shape.
The male gonads. Combined endocrine and exocrine glands that produce sex hormones and spermatozoids. The testis is in oval shaped and slightly flattened. They suspended outside of the abdomen cavity, Located inside a sac that made from skin and smooth muscle, called the scrotum.
two facts about testis u need to remember:
- The left testis is usually suspended lower than the right so the two are not compressed against each other.
2.human testis reside in the scrotum, because testis cannot produce spermatozoids at the core body temperature of 37o, they must by held at 35o
mechanism of regulating temperature of testis
The cremaster muscle – strips of the internal abdominal oblique muscle that enmesh the spermatic cord. When it is cold, the cremaster contracts and draws the testes closer to the body to keep them warm. When it is warm, the cremaster relaxes and testes are suspended farther from the body
tunica vaginalis:
Its anterior and lateral surfaces are covered by the tunica vaginalis a saccular extension of the peritoneum.
The testis itself has a white fibrous capsule called
tunica albugine
Stroma (connective tissue) extend from the …. into the …. of the testis and dividing it to 200-300 wedge shaped lobules.
- capsule
2.parenchyma
each lobule contains:
1-3 seminiferous tubules
seminefrous tubules are:
thin ducts in which spermatozoids are produced.
structure of seminefrous tubules
The wall of the tubules contain spermatogene epithelium for the spermatocytes production.
what cells can we find between the seminefrous tubules, what’s their functions?
Between the seminiferous tubules there are brunch of interstitial cells that produce testosterone, the leydig cells.
seminiferous tubules lead into tubules network that called
rete testis
where is rete testis found
rete testis is embedded in the capsule testis on the posterior side (mediastinum testis).
what’s mediastinum’s function
It supports the rete testis and blood and lymphatic vessels of the testis in their passage into and out of the substance of the gland.
Spermatozoids partially mature in :
the rate testis (do not swim while they in the male body)
after the testis :
spermatozoids leaves the testis and travel through series of spermatic ducts to reach the urethra
what are the ducts?
Efferent ductules, epididymis and its duct, vas deferens duct and ejaculatory duct.
first duct and its function
Efferent ductules – 12 small efferent ductules that arise from the rate testis and carry spermatozoids to the epididymis (into the head region of the epididymis).
second duct and its function
Epididymis – a site of storage and maturation of the spermatozoids
epididymis structure and location
It attaches to the posterior side of the testis and consists of:
Head – at the superior end.
Body – long middle.
Tail – slender at inferior end of testis.
The duct of the epididymis is single coiled duct that …
reabsorbs about 90% of the fluid that is secreted by the testis.
After 20 days of maturation of the spermatozoids in the head and body of the epididymis,
the spermatozoids reach the tail of epididymis. And they are stored there, the storage is for 40-60 days, if they stay longer than that they are reabsorbed by the epididymis.
the epididymis duct turn 180o and become the
vas deferens duct
what is the vas deferens duct, pathway steps?
this is a muscular tube that pass upward from the scrotum and travels through the inguinal canal to enter the pelvic cavity. After passing between the urinary bladder and ureter, it turns downward behind the bladder and widens to form the ampulla.
It ends when it units with the seminal vesicle (the seminal glands, a pair tubular glands that located in the pelvis. They secrete fluid that partly composes the semen)
vas deferens structure:
The duct has very narrow lumen and thick wall of smooth muscle that innervated by sympathetic nerves.
vas deferens function
it transport mature sperm to the urethra in preparation for ejaculation
why is skin
seminal vesicle function
attaches to vas deferens near the base of bladder and produce sugar rich fluid that is fructose that provides sperm with energy and motility. it drains into the ejacuation duct.
The secretory portion is convoluted duct with branches that form a complex labyrinth.
Its duct called: excretorius duct, and it drains into the ejaculatory duct.
true
Ejaculatory duct
the connection of vas deferens duct and seminal vesicle create the ejaculatory duct. It pass through the prostate and drains into the prostatic part of the urethra.
prostate gland:
located below the urniary bladder that contributes additional fluid to the ejaculate, which nourish the sperm
bulbourethral gland
located on both sides of urethra just below the postate gland, produces a clear fluid that empties into the urethra to lubricate it and neutralize acidity that may be present due to drops of urine.
urethra
the tube that carries urine and semen outside the body.
when penis is erect, flow of urine is blocked from urethra allowing:
only semen to be ejaculated at orgasm
structure of sperm
head, acrosome containing enzymes to penetrate an egg body containing mitochondria to provide energy, tail(flagella).
penis function
erves to deposit semen into the vagina.
penis structure
Half is internal root and half is external shaft and glans.
The external portion is about 10-20 cm, the glans is the expanded head at the distal end of the penis with external meatus at its tip.
SEVEN UP
S- seminefrous tubules
E- epididymis
V- van deferens
E- ejaculatory duct
N- nothing
U- urethra
p- penis
why is the skin loose
The skin is loosely attached to the shaft and allowing expansion during erection, the skin continues over the glans as foreskin.
On the penis shaft there are:
sebaceous glands that secretes smegma, this is oily moisture substance that helps keep the glans moist and relieve sexual intercourse by acting as lubricant.
3 elongated erectile bodies that bounded by tunica albuginea (fibrous capsule)
- Single corpus spongiosum – passes along the ventral side of the penis and encloses urethra. Originates as bulb from pelvic floor and expands at the distal end to fill the glans.
- Two corpora cavernosa – separated by a septum, diverge as 2 arms (crus) that attach to the symphysis pubic.
3.The erectile tissues are spongy and contain blood sinuses (lacunae). The partitions between lacunas are trabeculae that composed of connective tissue and smooth muscle.
