The male reproductive system

1. The male reproductive system

2. Consists of the following organs 2 testes 2 Epidimides 2 Deferent ducts (vas deferens) 2 Spermatic cords 2 Seminal vesicles 2 Ejaculatory ducts 1 Prostate gland 1 Penis

3. The Penis The parts Root – in the perineum Body – surrounds the urethra Structure Formed by three cylindrical masses of erectile tissue and involuntary muscle Supported by fibrous tissue Covered by skin Rich blood supply The two lateral columns are called the corpora cavernosa The column containing the urethra is called the corpus spongiosum

4. The corpus spongiosum expands at the tip into a trangular structure – the glans penis Just above the glans the skin is folded upon itself and forms a movable double layer – the fore skin or prepuce Blood Supply Deep, dorsal and bulbar arteries of the penis branches of the internal pudendal arteries Venous drainage Internal pudendal and internal iliac arteries

5. Testes Testes are reproductive glands of the male. Situated in a sac called scrotum The scrotum is in front of the upper parts of the thigh and behind the penis Suspended in the scrotum by spermatic cords Outer – tunica vaginalis Middle – tunica albugenia – fibrous Inner – tunica vasculosa Convoluted loops composed of germinal epithelial cells – called seminiferous tubules. Produce – sperms

6. Between tubules groups of interstitial cells (of Leydig) They secrete the hormone testosterone At the upper pole of the testis the tubules combine to form a single tortuous tubule – the epididymis Epididymis continues as deferent duct (vas deferens) in the spermatic cord

7. The spermatic cords Two spermatic cords, one leading from each testis Consist of Testicular artery – from abdominal aorta – just below the renal artery Testicular venous plexus – passes into the abdomen – left vein opens into the left renal vein, and the right into the IVC Lymph vessels – drain into the paraaortic nodes Deferent duct (vas deferens) – 45 cm – goes through inguinal canal – ascends towards the posterior wall of the bladder – there joined by duct from the seminal vesicle ? ejaculatory duct nerves

8. They suspend the testes in the scrotum The spermatic cord passes through the inguinal canal Nerves – from D10, D11

10. Epididymis collects sperms from the testes Situated posterolateral to the testis Has a head and body Continues as vas deferens Vas deferens A tubular structure which transmits the sperms to the prostatic urethra

11. Travels through the inguinal canal and reaches behind the urinary bladder and is joined by the duct of the seminal vesicle. After the junction it is called the ejaculatory duct Ejaculatory duct opens into the prostatic duct Family planning operation - the vas deferens is cut in the scrotum - vasectomy

12. Ejaculatory Ducts Two tubes formed by the union of the duct from a seminal vesicle and a deferent duct Pass through the prostate gland Join the prostatic urethra Carry seminal fluid and spermatozoa to the urethra

13. Seminal vesicles Fibromuscular pouches lined with columnar epithelium Lie on the posterior aspect of the bladder Lower end : a duct ? joins vas deferens and forms an ejaculatory duct Ejaculatory ducts pass through prostatic urethra carrying seminal fluid and spermatozoa to the urethra The seminal vesicles secrete and expel a viscous fluid that helps to keep the spermatozoa alive

14. Male Urethra A tubular structure which conducts urine from the bladder to the exterior at the external urinary meatus at the tip of the penis In male it is a common pathway for the flow of urine and semen Parts Internal urethral meatus Prostatic urethra Membranous urethra – the shortest and narrowest – from the prostate gland to the bulb of the penis, after passing through the perineal membrane The penile urethra lies in the corpus spongiosum of the penis and terminates at the external urethral orifice in the glans penis

15. Two urethral sphincters The internal sphincter – smooth muscle at the neck of the bladder above the prostate gland The external sphincter – striated muscle fibres surrounding the membranous part

16. The Prostate Definition It is a gland which is present in the male in the pelvic cavity Situation In front of the rectum and behind the symphysis pubis. It surrounds the first part of the urethra Structure Outer fibrous covering A layer smooth muscle Glandular substance – columnar epithelial cells Prostatic fascia is a dense and tough membrane which completely invests the gland.- it is the areolar tissue of the pelvic fascia.

17. Applied anatomy Most of the gland lies behind the urethra. A midline groove posteriorly divides the gland descriptively into two “lateral lobes”. Groove felt PerRectally Rectal wall can be made to slide over the prostate. In advanced cancer the groove is obliterated and the rectal wall becomes fixed to the prostate Enlargement of the prostate may obstruct the urethra Hypertrophy of the prostate is usually not a generalized hypertrophy of the whole gland, but the growth of an adenoma within it. The surrounding prostate becomes condensed around the adenoma. Prostatectomy – shelling out the adenoma from the peripheral condensed prostatic tissue Function It secretes a thin lubricating fluid that passes into the urethra through numerous ducts

18. Blood Supply Inferior vesical artery branches of the internal iliac artery Middle rectal artery Prostatic artery

19. Lymphatic drainage To the internal iliac nodes

20. Penis Root – in the perineum Body – surrounds the urethra Formed by three cylindrical masses of erectile tissue and involuntary muscle – corpora cavernosa and corpus spongiosum containing urethra – at the tip expanded into a triangular structure called the glans penis The erectile tissue is supported by fibrous tissue and covered by skin It has rich blood supply

21. Above the glans penis the skin is folded upon itself and forms a movable double layer the prepuce. Arterial blood supply – deep , dorsal and bulbar arteries of the penis – branches of internal pudendal arteries. Venous drainage to the internal pudendal and internal iliac veins Nerve supply – internal pudendal nerves, genitofemoral nerves – both auronomic and somatic nerves – parasympathetic stimulation leads to engorgement with blood and erection of the penis.

23. Urethra and penis