Download Male urethra

The Male Reproductive System
SHANDONG UNIVERSITY
Liu Zhiyu
The Male Reproductive System
Composion:

Internal genital organs
Gonad-testes
The duct of conveying sperms: includes
Epididymes Ductus deferens
duct
Male urethra
Accessory glands

External genital organs
Scrotum
Penis
internal genital organs
(一)Gonad
–testis
Paired, ovoid organs,
Located in scrotum
1.Shape
Superior extremity
Inferior extremity
Anterior borfer
Posterior border
Medial surface
Lateral surface
1.Shape of the testes
Superior
extremity
posterior
border
inferior
extremity
Anterior
border
(一)testis
2. Structure

tunica albuginea
mediastinum testis sends
numerous fibrous septules
into the gland, dividing it into
100～200 testicular
lobulesthat contain 2～4
contorted seminiferous
tubules → traight
seminiferous tubules
→rete testis
contorted
seminiferous
tubules
straight
seminiferous
tubules
rete testis
1.testis
2. Structure

efferent ducts of testis,
12 ～15 in number

Function of epididymis:
Produces sperm
secrete androgens
(二) Genital ducts
1. Epididymis
Shape：Comma-shaped,
head of epididymis
body of epididymis
tail of epididymis
Position：Located on
superior extremity and
posterior border of testis
Function – the site of
accumulation and storage of
sperm
2. Ductus deferens
Muscular tube that
transports sperm form
epididymis to ejaculatory
duct



Four part:
Testicular part
－extends form the tail
of epididymis to the
superior extremity of
testis
2.Ductus deferens

Spermatic part
－ form superior
extremity of testis to the
superficial inguinal ring,---- where the vasectomy
is performed
Inguinal part －
extends form superficial
to deep inguinal rings

2.Ductus deferens
Pelvic part －
crosses the ureter to
reach the base of
bladder, terminal part
dilates, -----ampulla
ductus deferentis

Spermatic cord


Extends from the superior
extremity of testis to the
deep inguinal ring
spermatic cord comprise:
Ductus deferens
Testicular artery
Pampiniform plexus of vein
Nerves and lymphatic
vessels
Vestige of vagina process
Spermatic cord
These structures are enclosed
by 3 layers of tunic



internal spermatic fascia
cremaster
external spermatic fascia
3.Ejaculatory duct


Formed by union of distal
portion ductus deferens
and excretory duct of
seminal vesicle
Passes through the upper
part of prostate and opens
into the prostatic part of
urethra
ejaculatory duct
(三) Accessory
glands
1.Seminal vesicle



Paired sacculated,
coiled glands
Secrete part of seminal
fluid
Located on posterior
surface of bladder,
lateral to ampulla
ductus deferens
seminal vesicle
2.Prostate
position
 Lies behind pubic
symphysis, between neck of
bladder and urogenital
diaphragm
 Shape
 Chestnut-shaped organ
Base of prostate
peostate
Apex of prostate
Body of peostate
Anterior surfaces
Posterior surfaces－prostatic
sulcus
2.Prostate
Contains of five lobes
Anterior lobe
Middle lobe
Posterior lobe
Right and left lobes
Capsule of protate
Sheath of protate
formed by pelvic fascia
3.Bulbourethral gland
－two small pea-shaped glands, located in the deep
transverse muscle of perineum, opens into bulb of
urethra
bulbourethral gland
External genital organs
(一) Scrotum

Pouch of thin skin lying
below the root of the penis

Divided into two haves by
septum of scrotum, contains
testes and epididymis
External genital organs
(一) Scrotum

The wall of the testis consist
of skin and dartos coat, a
connective tissue layer that
contains many smooth
muscle fibers which is
contineus anteriorly to the
scarpa’s fascia of abdomen
and posteriorly with Colles
fascia of perineum
The coverings of testis and spermatic cord
Parietal peritoneum
Transvers fascia
Trasversus abdominis
Obliquus internus
abdominis
Aponeurosis of obliquus
externus abdominis
External spermatic fascia
Cremastter
Parietal layer
Visceral
layer
Internal spermatic fascia
Tunica vaginalis of testis
Vaginal
cavity
(二)

Penis
division:
root
body
glans penis
• Consists of
Cavernous body of
penis: 2
Cavernous body of
urethra : 1
(二) Penis
Skin－thin and loose
Prepuce of penis
Frenulum of prepuce
(三)
Male urethra
Three parts

Prostatic part －lies
within the prostate

Membranous part– lies
within the urogenital
diaphragm surround by the
sphincter of urethra

Cavernous part －
transverse the all length of
cavernous body of urethra
(三)
Male urethra
Posterior urethra
prostatic part
membranous part
Anterior urethra
cavernous part
(三)
Male urethra
Three constrictions



internal urethral orifice
membranous part
external orifice of
urethra
Three enlarged parts



At prostatic part
At bulb of urethra
At navicular fossa of
urethra
(三)
Male urethra
Two curvatures
Subpubic curvature －concave upward
Prepubic curvature －concave downward
(三)
Male urethra
Within prostatic part
Urethral ridge
Seminal colliculus
Prostatic utricle
orifices of the ejaculatory ducts
gubernaculum of tastis
vagianal process
vagianal ligament
tunica vaginalis of tastis
parietal layer
visceral layer
vaginal cavity
ampulla ductus
deferentis
Spermatic part