Urinary System & Male Genital System
Dezhi Wang Department of Anatomy, Medical School of Wuhan University
Manneken Pis, a small bronze statue of a little boy peeing, is one of Brussels most famous landmarks.
Q:
1. Which organ produces urine? 2. To transport urine to the environment, how many organs serve as
URINARY SYSTEM Composing and functions: Kidney \u80be produce urine
Urinary tract
Ureter \u8f93\u5c3f\u7ba1 carry urine to the bladder Urinary bladder \u8180\u80f1 stores urine temporarily Urethra \u5c3f\u9053 carry urine to the outside genital functions (male) Other functions : Regulating blood volume and blood pressure by adjusting the volume of water lost in urine\u2026 Regulating ions in blood by controlling the quantities lost in urine\u2026 Helping to stabilize blood pH Helping the liver to detoxify poisons such as urea and uric acid\u2026
Features of kidneys bean-shaped, the size : 10cm x 5cm x 4cm Two extremities: Superior extremity (broader) Inferior extremity (thicker)
Two surfaces: Anterior surface (convex) Posterior surface (plane)
Two borders: Lateral border (convex) Medial border (concave) Renal hilum nerves
a slit where vessels and enter and leave the kidney the structures Main structures
ant. post. V A sup. A V
Renal pedicle which pass through the renal hilum and the connective tissue Renal sinus an internal cavity within the kidney, containing
P inf. P
Coverings of kidney Three layers (from inside to outside)
Maintaining the kidney’s shape and forming a barrier from the surrounding region
Fibrous capsule: a layer of fibers that covers the outer surface of kidney closely Adipose capsule: a thick layer of adipose tissue
act as a soft cushion
Renal fascia: a dense, fibrous outer layer which enclose the kidneys and suprarenal gland, can be divided into anterior and posterior layers Fibers from the renal fascia cross the adipose capsule to the fibrous capsule to fix the kidney
Location of kidneys
The kidneys are located on the posterior abdominal wall, either side of the vertibral column. The kidneys extend from the level of the 11th or 12th thoracic vertebra superiorly to the third lumbar vertebra inferiorly. The 12th ribs are behind the posterior surface of the kidneys The right kidney Lies slightly inferior to the left kidney
Structure of kidney
Renal cortex Renal column
The superficial area Inward extensions of the renal cortex
Structure of kidney urine Renal papillae Papillary foramina Minor renal calices Major renal calices Renal pelvis Becomes narrow
Ureter
ureter Junction of ureter and the renal pelvis Abdominal part
Three parts
Pelvic part Intramural part
terminal part of left common iiliac A. beginning of right external iiliac A. Junction of ureter and the wall of bladder Ureteric orifice
ureter
Junction of ureter and the renal pelvis
Abdominal part
Three parts
Pelvic part Intramural part
terminal part of left common iiliac A. beginning of right external iiliac A. Junction of ureter and the wall of bladder Ureteric orifice
The narrowest place
The first narrowed place
Kidney stones tend to lodge in the three narrowed places
A radiographic view of the urinary system (Posterior view. Obtained by taking an x-ray of the kidneys after a radiopaque compound has been administered.)
The second narrowed place
location of urinary bladder Empty bladder Lies entirely within the pelvis Posterior to the pubic symphysis Anterior to the rectum (male) or the vagina and uterus (female)
Full bladder roughly spherical and expands superiorly into the abdominal cavity
Features of empty bladder Empty bladder has the shape of an upside-down pyramid with four parts
Apex, fundus, body and neck
four triangular surfaces four angles
and
Structure of urinary bladder Trigone of bladder A triangular smooth area at the base of the bladder between the openings of the two ureters and that of the urethra Each year in the US, approximately 52,000 new cases of bladder cancer are diagnosed, and millions of new cases in India and China. The bladder cancer rate is highest among cigarette smokers and employees of chemical and rubber companies.
Interureteric fold
A fold of mucous membrane between the ureteric orifices It is the landmark to find the ureteric orifices when the urinary bladder is examined with cystoscope in the living body
The trigone is of special clinical importance because infections and cancers tend to persist in this region
Urethra Extends from the neck of the urinary bladder to the exterior, between internal and external urethral orifice.
Male urethra has three parts Female urethra
short and straight
Urinary tract infections occur in about 40% of women. Most urinary tract infections occur in sexually active young women, because intercourse drives bacteria from the vagina and the external genital region (and from the anus as well) through the nearby opening---the short urethra and toward the bladder. The infection of the bladder, can spread superiorly to infect the ureters and kidneys.
Urethral sphincter Internal urethral sphincter: A thickening of the smooth muscle around the internal urethral orifice
External urethral sphincter: A circular band of skeletal muscle in the urogenital diaphragm, which can be used voluntarily to inhibit urination until the proper time.
Male genital organs Internal genital organs Testes
Gonad
Produce sperms and sex hormones Epididymis (store Reproductive sperms) Ductus deferens duct Ejaculatory duct Serve as Urethra passageway of sperms; stores sperms Accessory glands
Seminal vesicles Prostate gland Bubourethral glands
Secrete the fluid to maintain the nutrition and activity of the sperms
External genital organs Scrotum
House the testes
Testes and epididymis testes
shape: flattened egg with two extremities, two surfaces and two borders Size: 4cm x 3cm x 2cm
Tunica albuginea Septa testis Lobules of testis Seminiferous tubules sperms
Testes and epididymis
sperms Rete testis Efferent ductules of testis Head of epididymis Body of epididymis
epididymis
Tail of epididymis
Ductus deferens
Ductus deferens The level of tail of epididymis Testicular part
The shortest part The level of head of epididymis
Four parts
Funicular part
Can be palpated easily The superficial inguinal ring
Inguinal part
Lies in the inguinal canal The deep inguinal ring
Pelvic part
The longest part The junction of the semianl vesical and ductus deferens
Spermatic cord and scrotum Spermatic cord
Contents
Deep inguinal ring
Ductus deferens Testicular artery Pampiniform plexus of vein Nervous plexus Lymphatic Vessels
upper extremity of testis
Spermatic cord and scrotum Covering of testis
Skin Scrotum Dartos External spermatic fascia Cremaster Internal spermatic fascia
Covering of Spermatic cord
Sperm cannot be produced at the core body temperature of 37℃ , the scrotum’s superficial position provides an environment that is about 3 ℃ cooler, an essential adaptation. Furthermore, the scrotum responds to changes in external temperature. If the external temperature is too high…
Seminal vesicles and ejaculatory duct Seminal vesicle
location
Posterior to the fundus of urinary bladder The yellow secretion constitutes 60% of the volume of semen
The end of ductus deferents
Excretory duct of seminal vesicle
Ejaculatory duct Open into Prostatic urethra
Prostate gland Inferior Superior Posterior Anterior
location
to the neck of urinary bladder to the urogenital diaphragm to the pubic symphysis to the ampulla of rectum
Three parts
Apex of prostate Base of prostate Corpus glandulae
The milky secretion constitutes about 1/3 of the volume of semen
Prostate enlargement occurs in about 50% of men at age 50 and 80% of men at age 70. It often begins with the hesitation to urinate, a weak stream and increased urinary urgency and frequency and may cause urinary obstruction finally. A digital rectal exam can help diagnose the disease, because there is a shallow sulcus lies in the midline of the posterior wall of prostate, the shallow sulcus disappears when the
Bulbourethral gland Pea-sized glands (round and with the diameters approaching 10 mm inferior to the prostate, within the urogenital diaphragm The bulbourethral glands produce a thin, clear fluid, some of which enter the spongy urethra when a male becomes sexually excited prior to ejaculation. which constitutes less than 5% of the volume of semen.
magnify
penis
Three parts:
Glans of penis: thickened distal end Body of penis: the movable portion
Neck of penis
Root of penis: the posterior portion
Covering Prepuce
skin and fascia the folded skin upon the neck and glans
Orifice The free border of of the prepuce prepuce Cavernous bodies Long cylindrical erectile bodies Covered with albuginea Two cavernous body of penis The proximal end
crus penis
One cavernous body of urethra The enlarged distal end
glans penis
male urethra Prostatic portion
Anterior urethra Posterior urethra
pierces the prostate
Urethral crest: a longitudinal mucosal fold on the posterior wall Seminal colliculus: a prominence on the urethral crest Openings of ejaculatory duct, prostate Membranous portion Cavernous portion
pierces the urogenital diaphragm pierces the Cavernous body of urethra
Two curves the prepubic curve the subpubic curve Three constriction the internal orifice the membranous portion the external orifice Three dilated places
the prostatic portion the bulbous portion of urethra
