Human System Of Reproductive-male

Male Reproductive System

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Male Reproductive System

Primar y Sex Organ Testis

Accessory Sex Organs External Genitalia Penis: Organ of Copulation Scrotum

Genital Ducts: Genital Glands: Epididymis Prostate Vas deferens Seminal vesicle Ejaculatory duct Bulbourethral Urethra

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) 1) 2) 3) 4) 5) 6) 7)

Skin (scrotum) Dartos muscle Colle's fascia External spermatic fascia Cremasteric muscle & fascia Internal spermatic fascia Tunica vaginalis: – parietal layer & visceral layer 8) Tunica albuginea (fibrous capsule) 9) 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.

Blood Supply

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

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 Scrotal swelling: Varicocele, Inguinal hernia, Hydrocele or may extend down into the scrotum 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 of dartos muscle 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 the development & storage of the sperms.

Spermatic Cord

• The spermatic cord is a collection of structures that pass through the inguinal canal to 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 processus vaginalis

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

• It is a highly coiled tube 6 meters) • Forms a commacomma 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.

Epididymis

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

Vas Deferens • It Is a cord like structure 45 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. vesicle It opens in the prostatic urethra. 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

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

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

Glans Corpora cavernosa Corpus spongiosum

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

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.