The Urinary System
MEDL 2350
Lecture 3
February 17, 2003
Functions
 The urinary system consists of 2 kidneys,
2 ureters, a urinary bladder, and the
urethra.
 The urethra has distinct functions
depending on the sex (gender) of the
individual.
 The female urethra has ONLY a urinary
function.
 The male urethra has both urinary and
reproductive functions.
 In both sexes, the main function of the
urinary system is the eliminate waste
products from the body.
The Functions
 Maintain HOMEOSTASIS, or a constant
internal environment.
 Maintain constant concentrations of salt,
water, and acids.
Anatomy of the Urinary
System
 Blood enters the kidneys through the RENAL
ARTERIES and leaves the kidneys through the
RENAL VEINS.
 Blood is filtered in the GLOMERULUS.
 The glomerulus is part of the functional unit of
the kidney called the NEPHRON.
 The nephrons are contained within the RENAL
CORTEX and RENAL MEDULLA.
 Urine is collected in the CALICES
(singular – CALYX).
 From the calices (located within the
RENAL PELVIS) the urine enters the
URETERS.
 The ureters connect the kidneys to the
bladder.
 Within the bladder, urine is stored until there is
enough pressure to cause it to enter the
urethra.
 The urethra carries urine from the bladder to
the outside world.
 The male urethra has three parts:
1. penile urethra – within the penis
2. membranous urethra – within the
urogenital diaphragm
3. prostatic urethra – within the prostate gland
 The female urethra is very short and is
located superior to the vagina.
Urinary Combining Forms
Combining
Form
Meaning Example
Cyst / o
bladder
Cyst / o / scope
Instrument to view
the bladder
Ureter / o
ureter
Ureter / o / lith
A stone or calculus
in the ureter
Glomerul / o
glomerulus
Glomerul / o/ pathy Disease of the
glomerulus
Nephr / o
kidney
Nephr / itis
Inflammation of the
kidney
Ren / o
kidney
Ren / al
Pertaining to the
kidney
Pyel / o
Renal pelvis
Pyel / lith /o/ tomy An incision in the
Urethr / o
urethra
Urethr /o/ dynia
Ur / o
urine
Ur / emia
Urin / o
urine
Urin / ary
renal pelvis to
remove a stone
Pain in the
urethra
Blood in
the urine
Pertaining
to the urine
Some Suffixes
-osis
-pathy
-pexy
-ptosis
abnormal condition
disease
fixation
falling
Abnormal condition
Enlargement
Hardening
-osis
- megaly
- scler
What does each word mean?
Nephromegaly
Enlargement of the kidney
Nephrectomy
Removal of the kidney
The suffix –iasis is used to describe
something abnormal.
An abnormal condition of kidney stones is
Nephr / o / lith / iasis
kidney
stone
Abnormal
condition
Combine nephr / o and -ptosis
Nephroptosis
Which means a dropping or prolapse of a
kidney.
The Ureters, Bladder, and
Urethra
 Urine is conveyed from each kidney
through one of two ureters and stored in
the bladder until it is removed from the
body through the urethra.
The suffix -ectasis means dilation or
enlargement.
Therefore, an enlargement of the ureter is
called ureter / ectasis.
A stone in the ureter is a
ureterolith
You would use a procedure called a
ureter / o / lith /o / tomy
A surgical
procedure
ureter
stone
to remove a ureterolith.
 Stones are formed in the urinary tract by
the deposit of crystalline substances
excreted in the urine.
 Stones can be surgically removed or
crushed so the pieces are voided in the
urine.
 The suffix -tripsy means crushing.
 The urinary bladder is a muscular sac
that stores urine until it is removed.
 The combining forms cyst / o and
vesic / o are used to refer to the bladder.
Ureterolith
-> stone in the ureter.
Ureterocystoscope -> an instrument to
view the ureter and bladder.
Ureterocystoscopy -> visual
examination of the ureter and bladder.
 The urethra differs in men and women.
In men, it serves a dual function of
conveying sperm and urine. In females,
it only conveys urine.
 The combining form for urethra is
urethr / o
Cancers
 Malignant tumors are cancerous.
 Benign tumors are non-cancerous.
 Malignant tumors spread rapidly.
 The combining form adeno / o
Is used to denote a gland.
Therefore, adeno / o / dynia
is a word that denotes pain in a gland.
 The combining form carcin / o means
cancer.
 Therefore,
aden / o / carcin / oma
refers to a cancerous glandular tumor.
 A “UTI” refers to URINARY TRACT
INFECTION.
 UTI’s account for the majority of office
visits resulting from urinary symptoms.
The Nephron
 Each kidney contains about 1 million
NEPHRONS. These structures are the filtering
mechanisms of the kidney.
 The nephron is responsible for keeping fluid
levels balanced.
 Urine flows from the nephron into the funnelshaped CALYX.
 From the calyx, urine passes into the RENAL
PELVIS to the ureter.
 The combining form
pyel / o
refers to the renal pelvis.
Parts of the Nephron
 Glomerulus
 Collecting tube
 Bowman’s Capsule
The combining form
glomerul / o
refers to the glomerulus.
Combining Forms for Color
Erythr / o
->
red
Leuk / o
->
white
Combining Form for
Infection
 PUS is a collection of dead blood and
inflammatory cells.
 The combining form that means pus is
py / o
 The suffix
-uria
refers to urination.
Hemat / uria ->
blood in urine
py / uria
pus in the urine
->
The combining form
olig / o
refers to scanty or little.
Therefore, olig / uria means little or
scanty urination.
Miscellaneous
The combining form for night is
noct / o
The suffix -phobia means fear.
The prefix in- refers to “not”.
Other Urinary Disorders
AZOTURIA - an increase in nitrogen in the urine.
DIURESIS – abnormally large amount of urine.
ENURESIS – involuntary discharge of urine after the age
which bladder control should have been established.
HYPOSPADIAS – abnormally place urethral opening on
the underside of the penis.
PHIMOSIS – stenosis (narrowing) of the
foreskin opening over the glans of the
penis.
UREMIA – elevate level of waste products
in the blood.