Human System System Of Male Reproductive

Male Reproductive System
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Primary
Sex Organ
Testis
Accessory Sex Organs

Function of the Male Reproductive System

Primary sex organs:
Gonads (testes): produced:
Gametes: sperms
Sex hormone: testosterone
Genital Ducts: store sperm &transport sperms
Accessory glands: secrete substances that nourish the sperms
External genitalia:
Penis: organ of copulation
Scrotum: protect testis

Testes

They are the 1ry sex organ which produce:
spermatozoa (exocrine function)
& testosterone hormone (endocrine function).
Location:
small oval organ located in the scrotum suspended by spermatic cord

Coverings Of The Testes

Each testis has the following coverings:
3 capsules:
tunica vasculosa
tunica albuginia:fibrous layer, which thickened posteriorly to form mediastinum testis
tunica vaginalis: serous layer ,which has visceral & parietal layers

3 coats derived from anterior abdominal wall:
Internal spermatic fascia: derived from the fascia transversalis
Cremasteric muscle and fascia: derived from the internal oblique muscle
External spermatic fascia: derived from the external spermatic aponeurosis

The Covering Of The Testis (From Outside To Inside)
Skin (scrotum)
Dartos muscle
Colle's fascia
External spermatic fascia
Cremasteric muscle & fascia
Internal spermatic fascia
Tunica vaginalis: – parietal layer & visceral layer
Tunica albuginea (fibrous capsule)
Tunica vasculosa

The Covering Of The Testis (From Outside To Inside)

Internal Structure Of The Testis
From the medistinum testis septa arise and dividing the testis into 250 lobules each lobule contains 1-4 convoluted seminiferous tubules(60 cm in length)

Connective tissue between the tubules contains interstitial cells of Leydig which secrete testosterone
Spermatogenic cells: produce sperms
Sertoli cells: supporting
The seminiferous tubules join to form straight tubules called tubuli recti
Which break into a network of canaliculi called rete testis.

Arterial supply: Testicular artery which is a branch from abdominal aorta at the level of the 2nd lumbar vertebra.
Venous drainage: pampiniform plexus of veins, becomes:

The right testicular vein &drains into the inferior vena cava,
left testicular vein drains into the left renal vein

Blood Supply

Lymph Drainage of the Testis & Scrotum
The lymph drainage of the testis and epididymis is into the lumbar or paraaortic lymph nodes at the level of the first lumbar vertebra.
The lymph drainage of the scrotal wall is into the superficial inguinal lymph nodes.

Clinical Notes:1-Varicocele

A varicocele is a condition in which the veins of the pampiniform plexus are elongated ,dilated and tortuous.
It is a common disorder in young adults, with most occurring on the left side.
This is thought to be because the right testicular vein joins the low-pressure inferior vena cava, whereas the left vein joins the left renal vein, in which the venous pressure is higher.

Cryptorchidism: Undescended Testis:
One of the testes may fail to descend into the scrotum during development.

Imperfect descent (Cryptorchidism)
Incomplete descent:
in which the testis, although traveling down its normal path, fails to reach the floor of the scrotum. It may be found within
The abdomen, within the inguinal canal, at the superficial
inguinal ring, or high up in the scrotum.
It is necessary for the testes to leave the abdominal cavity
because the temperature there retards the normal process
of spermatogenesis. If an incompletely descended testis is
brought down into the scrotum by surgery before puberty, it
will develop and function normally. A maldescended testis,
although often developing normally, is susceptible to traumatic injury and, for this reason, should be placed in the
scrotum.
The incidence of tumor formation is greater in testes that have not descended into the scrotum.

Hydrocele: This is an accumulation of fluid within the tunica vaginalis.
The indirect inguinal hernia: the protrusion of part of the abdominal contents into the inguinal canal &scrotum
It is congenital in origin (the remains of the processus vaginalis). The hernial sac enters the inguinal canal through the deep inguinal ring and lateral to the inferior epigastric
vessels. The hernial sac may extend down into the scrotum
Scrotal swelling: Varicocele, Inguinal hernia, Hydrocele or testicular tumor

The Scrotum
It is a sac of dark & wrinkled skin
It is divided by a septum into right & left compartments, each of which enclose:
a testis
The epididymis
The lower end of the spermatic cord

The wall of the scrotum has the following layers:
Skin; dartos muscle; Colles’ fascia; external spermatic fascia; cremastric muscle &fascia; internal spermatic fascia& tunica vaginalis
the dartos muscle is innervated by sympathetic nerve &contraction ofdartosmuscle wrinkles the scrotum & reducing heat loss.
The external location of the testis in the scrotum brings the tests in an environment with a temperature less than the body by 1.5-2 degree, a condition necessary for thedevelopment & storage of the sperms.

Spermatic Cord
The spermatic cord is a collection of structures that pass through the inguinal canalto and from the testis.
It is covered with 3 concentric layers of fascia derived from the layers of the anterior abdominal wall.
It begins at the deep inguinal ring& ends at the testis.
Structures of the Spermatic Cord:

Vas (ductus) deferens
Testicular artery
testicular vein (Pampiniform plexus)
Testicular nerve (Autonomic)
Testicular lymph vessels
Remains of processusvaginalis

The Coverings Of The Spermatic Cord

External spermatic fascia: is derived from the external oblique aponeurosis
Cremasteric muscle & fascia: derived from the internal oblique muscle
Internal spermatic fascia: is derived from transversalis fascia

Pathway of Sperm
Seminiferous tubules
Rete testis
Epididymis
Vas (ductus) deferens
Ampulla of vas deferens
Ejaculatory duct
Prostatic urethra
Membranous urethra
Penile (spongy) urethra

Genital Ducts
Conduct the sperms from the testis to the urethra.
They allow the maturation & storage of spermatozoa
They include:

Tubuli recti.
Rete testis.
Efferent ductules.
Duct of Epididymis
Vas deferens
Ejaculatory ducts
urethra

Epididymis
It is a highly coiled tube 6 meters)
Forms a comma- shaped structure in relation to the posterior part of testis.
It is formed of the following parts:
Head: the upper part that forms a cap around the upper pole of the testis.
Body: the middle part behind the testis.
Tail: the lower part which is continuous with the vas deferens.

The sperms stored & complete their maturation in epididymis until ejaculation.

Vas Deferens
It Is a cord like structure45 cm tube with thick muscular wall
It transmits the sperms from the epididymis to the ejaculatory duct.
1-It begins in the scrotum as a continuation of the tail of the epididymis behind the testis.
It ascends in the spermatic cord
2- It enters the inguinal canal
At the deep inguinal ring, it hooks around the lateral side of the inferior epigastric artery to enter the pelvis.

3-Then, it passes on the side wall of pelvis crossing the following from above down:
External iliac vessels
Umbilical artery
Obturator nerve & vessels
Then, it passes medially crossing over the ureter and descends behind the base of urinary bladder medial to seminal vesicle where it forms the ampulla of vas.
It join the duct of seminal vesicle to form ejaculatory duct.
Vasectomy:male sterilization is done by vasectomy, where a short segment of vas is cut through an incision in the upper part of the scrotum .

Ejaculatory Duct

Formed by union of the ampulla of the vas deferens with the duct of the seminal vesicle.
It opens in the prostatic urethra.
Urethra:
Is a common passageway for urine and semen.

Accessory Glands
Are the glands that secrete substances into the passageways that transport sperms.
These substances contribute to liquid part of semen.
They include:
Seminal vesicle
Prostate
Bulbourethral (Cowper’s) glands

Seminal Vesicle

They are in the form of sacculated glands 5 cm long
lying behind the urinary bladder, lateral to the ampulla of vas& anterior to the rectum.
Formed of highly coiled tube
Its duct joins the vas deferens to form ejaculatory duct
Its secretion constituting 60% of semen. This secretion is alkaline & contains fructose.

Prostate Gland

Single gland (2,3,4cm)
Site: lies below the neck of urinary bladder
behind the lower border of symphysis pubis
surrounding the upper part of the urethra (prostatic urethra).

Shape: inverted cone which has:
Apex.
Base.
4 surfaces.

Apex: directed downwards
Base: directed upwards. It is directly with the bladder neck. It is pierced by the urethra
Posterior surface:related to ampulla of rectum
It is pierced by 2 ejaculatory ducts
Anterior surface:
lies behind
the lower
border of
Symphysis
pubis

Prostate Gland

Its ducts open along the urethral crest
It produces an acidic secretion, which is add to the (25%) semen during ejaculation
The urethra & 2 ejaculatory ducts traverse the prostate; dividing it into 5 lobes:

Lobes:1. Median:It lies between the urethra and the 2 ejaculatory ducts. It projects inside the urinary bladder forming “uvula vesicae” just behind the internal urethral meatus. It contains much glandular tissue (common site of adenoma). 2.Anterior, 3.Posterior 4.Right & 5. left lateral lobes

Hypertrophy Of Prostate With Age

The prostate undergo hypertrophy with age (50 y) resulting in benign hyperplasia, a condition that may constrict the urethra resulting in difficulty in urination
Per rectal examination of the prostate

Bulbourethral (Cowper’s) glands:
They are small gland that lie on either side of membranous urethra. They open into penile urethra. They produce alkaline secretion that protecting the sperms & lubricate the tip of the penis

Penis: Erectile Bodies
It is the copulatory organ in man that passes urine & semen.
It is a highly vascular cylindrical organ
Glans

Erection is by parasympathetic nerves.
Ejaculation: is by sympathetic nerves.

Corpora cavernosa
Corpusspongiosum
Bulb of penis
Crus of penis

It consists of a :
Root: that attach penis to perineum
A body (shaft):
Glans penis: enlarged end of the body. Prepuce (foreskin): partially covers glans and surrounds external urethral meatus (may be removed in circumcision)

Internal Structure Of The Penis
It consists of 3 masses of erectile tissue:
2 corpora cavernosa
Corpus spongiosum: is traversed by the urethra & its posterior end expand to form the bulb of the penis.