Structure of the Male Reproductive System

Male Reproductive System

testes, epididymis, vas deferens, penis, seminal vesicles, prostate gland, bulbourethral gland, urethra. penis and srotum

testes (testicles)

Lies obliquely—upper pole tilted forwards & laterally, lower pole backwards & medially

The left testis is slightly lower than the right

suspected in the scrotum by the spermatic cord

appendix testis

the testicular appendage located between the head of the epididymis and the superior pole of the testis

Coverings of testes

tunica vaginalis, tunica albuginea, septa

tunica vaginalis

outer layer derived from peritoneum

tunica albuginea

capsule that surrounds each testis. posterior thickened- mediastinum testis

septa testis

extensions of the capsule that extend into the testis and divide it into lobules

seminiferous tubules (testes)

highly coiled

produce sperm

straight tubules (tubuli recti)

connect seminiferous tubules to rete testis

rete testis

network of tubules between the seminiferous tubules and the epididymis

efferent ductules of testis

connect rete testis to epididymis

epididymis duct

Found on the superior part of the testis and along the posterior lateral side

blood supply of testes

testicular arteries, pampiniform plexus,

lymphatic drainage of testes

preaortic & paraaortic groups

spermatic cord

extends upward from the epididymis and is attached to each testicle.

coverings of spermatic cord

External spermatic fascia

Cremaster muscle and fascia

Internal spermatic fascia

contents of spermatic cord

-vas deferens

-testicular artery

-pampiniform plexus of veins

-nerve

Nerves of spermatic cord

- genital branch of genitofemoral nerve

- testicular plexus

The duct system of the male reproductive system

epididymis, ductus (vas) deferens, urethra

Epididymis

Comma-shaped, tightly coiled tube

Expels sperm with the contraction of muscles in the epididymis walls to the vas deferens

Epididymis parts

Head (caput)

Body (corpus)

Tail (cauda)

ductus (vas) deferens

extends from the epididymis to the urethra; propels sperm into the urethra by peristalsis during ejaculation.

Passes over the bladder

external vas deferens

from the lower pole of testes as a continuation of the epididymis to rim of inguinal canal

inguinal canal

the channel through which the testis descends into the scrotum in the male

internal vas deferens

from lateral wall of pelvis to ampulla of base of urinary bladder where it is joined by the seminal vesicle to form ejaculatory duct which empties into prostatic urethra.

ejaculatory duct

small duct that connects the vas deferens to the urethra

Urethra (male)

tube from bladder to outside of body also carries semen to outside.

prostatic urethra.

passes through the prostate gland

membranous urethra (male)

passes through urogenital diaphragm

spongy (penile) urethra

passes through the penis and opens via the external urethral orifice

Accessory organs of the male reprodutive system

Seminal vesicles

Prostate

Bulbourethral glands

seminal vesicle

A blind-ending, coiled, and sacculated tube on both sides.

male organ that produces seminal fluid for sperm cells. ( ~60% total volume of semen.)

Prostate gland

a gland surrounding the neck of the bladder in male mammals and releasing prostatic fluid. (slightly alkaline fluid that activates the sperm and prevents them from sticking together)

what type of tissue is the prostrate gland

fibromuscular glandular tissue.

capsule of prostate gland

-fibrous internally which is surrounded from outside by a fibrous prostatic sheath

is continuous with the puboprostatic part of the levator ani muscle

In between the prostatic capsule and the prostatic facial sheath lies the prostatic venous plexus.

the prostatic venous plexus.

covers prostate. anastamoses with vesical venous plexus. drains into vesical veins

relations of the prostate gland

Superior (Base)

neck of the urenary blader, Seminal Vesicles and Ejaculatory Ducts.

Inferior (Apex)

Urogenital Diaphragm

Anterior

Pubic Symphysis

Posterior

Rectum

Lateral

Levator Ani Muscles

Pubic Symphysis

cartilaginous joint at which two pubic bones fuse together

Lobes of the prostate

five lobes.

anterior lobe (isthmus)

Posterior lobe (infero-posterior)

Lateral lobes (R/L)

Median lobe (middle)

anterior lobe of the prostate (isthmus)

mostly muscle fibers from internal urethral sphincter

posterior lobe of prostate

part of the prostate that lies inferior to the ejaculatory dict and is most easily felt on rectal exam; common location for prostate cancer.

lateral lobes of prostate

On either side of urethra

Contain majority of glandular tissue

middle (median) lobe of prostate

between urethra and ejaculatory ducts. closely related to the neck of the urinary bladder.

Central zone of prostate

-Site of ejaculatory ducts.

is represented by the middle lobe.

peripheral zone of prostate

It forms the outer, back, and lower parts (posterior and lateral sides) of the prostate

Blood supply of the prostate

Arterial Supply:

inferior vesical artery (often referred to as the prostatic artery),

Venous Drainage:

Prostatic Venous Plexus

Prostatic Venous Plexus

Lies between the prostatic fibrous capsule and the prostatic sheath.

It drains into the internal iliac veins.

relations of the prostatic venous plexus

superiorly with the vesical venous plexus and posteriorly to the internal vertebral venous plexus.

lymphatic drainage of prostate

internal iliac nodes

Hypertrophy of the Prostate

Affects most older males, blocks the urethra leading to UTI and kidney Damage.

Treatments: surgery, drugs, microwaves, TUNA, "balloon option"

bulbourethral glands

the two glands below the prostate that secrete a sticky fluid that becomes a component of semen.

They secrete clear, viscous mucin that wash the urethra from the traces of acidic urine.

external genitalia

scrotum and penis

Scrotum

a pouch of skin containing the testicles.

Layers of the scrotum

1. skin: thin, sweat glands and vascular.

2. Dartos muscle (smooth, replaces fatty layer of superficial fascia )

3. Colle's fascia is the membranous layer of superficial fascia.

4.External Spermatic fascia.

5.Cremaster muscle (skeletal).

6. Internal spermatic fascia.

Penis

A tube-shaped organ that extends from the trunk of the body just above the testes.

contains 3 erectile bodies.

erectile bodies of penis

corpus cavernosum and corpus spongiosum

corpus cavernosum

two columns of erectile tissue in the shaft of the penis.

on its ventral surface.

corpora cavernosa

two columns of erectile tissue found in the shaft of the penis on its dorsal surface.

It is traversed by the spongy urethra

tough tunica albuginea

a tough, dense, fibrous sheath of connective tissue It encases the paired erectile chambers