Kidneys combining form
nephr/o, ren/o
Kidney function
Filter the blood to remove waste products, maintain electrolyte concentrations, and remove excess water to maintain the fluid volume within the body.
Renal Pelvis combining form
pyel/o
Renal pelvis function
Collects urine produced by the kidneys.
Urine combining form
ur/o, urin/o
Urine function
Liquid waste products to be excreted.
Ureters combining form
ureter/o
Ureters function
Transport urine from the kidneys to the bladder.
Urinary Bladder combining form
cyst/o
Urinary bladder function
Stores urine until it is excreted.
Urethra combining form
urethr/o
Urethra function
Transports urine from the bladder through the urethral meatus, where it is excreted.
Prostate combining form
prostat/o
Prostate function
A gland of the male reproductive system that surrounds the male urethra. Disorders of this gland can disrupt the flow of urine.
-cele
hernia, tumor, swelling
cyst/o
urinary bladder, cyst, sac of fluid
Dia-
through, between, apart, complete
glomerul/o
glomerulus
hydr/o
water
lith/o
stone, calculus
-lysis
breakdown, separation, setting free, destruction, loosening
nephr/o
kidney
pyel/o
renal pelvis, bowl of kidney
-tripsy
to crush
ur/o
urine, urinary tract
ureter/o
ureter
urethr/o
urethra
-uria
urination, urine
vesic/o
urinary bladder
urinary system performs many functions that are
important in maintaining homeostasis
Urinary system functions
Maintaining the proper balance of water, electrolytes, and acids in the body by filtering the blood as it flows through the kidneys; Constantly filtering the blood to remove urea, creatinine, uric acid, and other waste materials from the bloodstream; Converting these waste products and excess fluids into urine in the kidneys and excreting them from the body via the urinary bladder
Creatinine
waste product of muscle metabolism
urinary system or urinary tract consists of
two kidneys, two ureters, one bladder, and one urethra
genitourinary tract
because the urinary tract is located in close proximity to the reproductive organs
kidneys constantly
filter the blood to remove waste products and excess water. These are excreted as urine, which is 95% water and 5% urea and other body wastes
How much blood does the kidney filter per day
Roughly 150-200 quarts
How much urine is produced per day
1-2 quarts
kidneys other functions
maintain the proper level of fluid, produce hormones that control blood pressure and make red blood cells, and activate vitamin D to maintain healthy bones
renal (REE-nal) means
pertaining to the kidneys (ren means kidney or kidneys, and -al means pertaining to)
Where are kidneys located
retroperitoneal space, with one on each side of the vertebral column below the diaphragm and the lower edge of the rib cage
Retroperitoneal means
behind the peritoneum, which is the membrane that lines the abdominal cavity
renal cortex (REE-nal KOR-tecks)
the outer region of the kidney. This layer of tissue contains more than one million microscopic units called nephrons.
cortex means
the outer portion of an organ
medulla (meh-DULL-ah)
the inner region of the kidney, and it contains most of the urine-collecting tubules.
tubule
a small tube
nephrons (NEF-ronz)
the microscopic functional units of each kidney; it is here that urine is produced through the processes of filtration, reabsorption, and secretion
Reabsorption
the return to the blood of some of the substances that were removed during filtration
Each nephron contains
a glomerulus (gloh-MER-you-lus), which is a cluster of capillaries (plural, glomeruli), surrounded by a cup-shaped membrane called the Bowman's capsule, and a renal tubule
First step in the process of urine production
Blood enters the kidney through the renal artery and flows into the nephrons
Second step in the process of urine production
After passing through the filtration system of the glomerulus, the filtered blood containing protein and blood cells leaves the kidney and returns to the bloodstream through the renal vein
Third step in the process of urine production
The remaining filtrate flows into the renal tubules, where elements, including some water, sugar, and electrolytes, are returned to the bloodstream via a nearby capillary
Fourth step in the process of urine production
Remaining waste products are continuously converted into urine, which is transported to the renal pelvis and collected in preparation for entry into the ureters
renal pelvis
the funnel-shaped area inside each kidney that is surrounded by the renal cortex and medulla; where the newly formed urine from the nephrons collects before it flows into the ureters
ureters (you-REE-ters)
two narrow tubes, each about 10 to 12 inches long, which transport urine from the kidney to the bladder
How does urine move from the ureters to the bladder
Peristalsis, which is a series of wave-like contractions
How does urine get into the bladder
drains from the ureters into the bladder through the ureteral orifices in the wall of the urinary bladder
Orifice means
opening
urinary bladder
an oval, hollow, muscular organ that is a reservoir for urine before it is excreted from the body
Where is the urinary bladder located
in the anterior portion of the pelvic cavity behind the pubic symphysis
The average adult bladder stores how much urine
more than one pint
What is the bladder lined with
rugae, which allow it to expand when full and contract when empty
urethra (you-REE-thrah)
the tube extending from the bladder to the exterior of the body
Urinary sphincters
two, one on either end of the urethra; muscular rings control the flow of urine from the bladder into the urethra and out of the urethra through the urethral meatus
sphincter
ring-like muscle that closes a passageway
urethral meatus (you-REE-thrahl mee-AY-tus) or urinary meatus
the external opening of the urethra
meatus means
external opening of a canal
female urethra
approximately 1.5 inches long, and the urethral meatus is located between the clitoris and the opening of the vagina; transports only urine
male urethra
approximately 8 inches long, and the urethral meatus is located at the tip of the penis; transports both urine and semen
prostate gland (PROS-tayt)
part of the male reproductive system, surrounds the urethra; Most disorders of the prostate affect the male's ability to urinate
Urination
voiding or micturition; normal process of excreting urine
What causes the urge to urinate/micturate
As the bladder fills up with urine, pressure is placed on the base of the urethra
What is required for urination
the coordinated contraction of the bladder muscles and relaxation of the sphincters, which forces the urine through the urethra and out through the urethral meatus
nephrologist (neh-FROL-oh-jist)
physician who specializes in diagnosing and treating diseases and disorders of the kidneys (nephr means kidney, and -ologist means specialist)
urologist (you-ROL-oh-jist)
physician who specializes in diagnosing and treating diseases and disorders of the urinary system of females and the genitourinary system of males (ur means urine, and -ologist means specialist)
nephropathy (neh-FROP-ah-thee)
any disease of the kidney (nephr/o means kidney, and -pathy means disease); includes both degenerative and inflammatory conditions
Diabetic nephropathy
kidney disease resulting from poorly controlled diabetes mellitus
Renal failure or kidney failure
the inability of one or both of the kidneys to perform their functions; body cannot replace damaged nephrons, and when too many nephrons have been destroyed, the result is kidney failure
Azotemia (ay-zoh-TEE-mee-ah)
elevation of the blood urea nitrogen (BUN) caused by a lack of blood flow to each kidney; Uremia can occur when this excess becomes toxic
Uremia (you-REE-mee-ah)
uremic poisoning; toxic condition resulting from renal failure in which kidney function is compromised and urea and other waste products normally secreted in the urine are retained in the blood (ur means urine, and -emia means blood condition)
Acute renal failure (ARF)
sudden onset and is characterized by uremia; can be fatal if not reversed promptly.
How can ARF be caused
by the kidneys not receiving enough blood to filter due to dehydration or a sudden drop in blood volume or blood pressure from injury, burns, or a severe infection
Chronic kidney disease (CKD)
the progressive loss of renal function over months or years; may result from diabetes mellitus, hypertension, or a family history of kidney disease
CKD and vascular system
buildup of waste in the blood from chronic kidney disease can be a contributing factor in heart attacks and strokes
End-stage renal disease (ESRD)
kidney failure; the final stage of chronic kidney disease, and this condition is fatal unless the functions of the failed kidneys are replaced by dialysis, or with a successful kidney transplant
Nephrotic syndrome (neh-FROT-ick)
nephrosis; group of conditions in which excessive amounts of protein are lost through the urine; usually caused by damage to the glomeruli; results in abnormally low levels of protein in the blood (nephr/o means kidney, and -tic means pertaining to)
Edema (eh-DEE-mah)
excessive fluid accumulation in body tissues that can be symptomatic of nephrotic syndrome and other kidney diseases; can be in the area around the eyes, or in the legs and feet
Hyperproteinuria (high-per-proh-tee-in-YOU-ree-ah)
the presence of abnormally high concentrations of protein in the urine (hyper- means excessive, protein means protein, and -uria means urine)
Hypoproteinemia (high-poh-proh-tee-in-EE-mee-ah)
the presence of abnormally low concentrations of protein in the blood (hypo- means deficient or decreased, protein means protein, and -emia means blood condition); often associated with hyperproteinuria
Causes of nephrotic syndrome
diabetes mellitus, infection, and kidney disorders
most common cause of nephrotic syndrome in children
Minimal change disease, so called because the nephrons look normal under a regular microscope
ectopic kidney
congenital condition in which one kidney is located in an abnormal position or has fused with the other kidney (ec- means out, top means place, and -ic means pertaining to)
Ectopic means
located in an abnormal place or position
What is ectopic kidney associated with
increased risk of urinary tract infections and nephroliths
Hydronephrosis (high-droh-neh-FROH-sis)
the dilation (swelling) of one or both kidneys (hydr/o means water, nephr means kidney, and -osis means abnormal condition or disease)
Cause of hydronephrosis
problems associated with the backing up of urine due to an obstruction such as a nephrolith (kidney stone) or a stricture (narrowing) in the ureter
Nephritis (neh-FRY-tis)
inflammation of the kidney or kidneys (nephr means kidney, and -itis means inflammation)
Common cause of nephritis
toxins, infection, or an autoimmune disease
Glomerulonephritis (gloh-mer-you-loh-neh-FRY-tis)
type of nephritis caused by inflammation of the glomeruli that causes red blood cells and proteins to leak into the urine (glomerul/o means glomeruli, nephr means kidney, and -itis means inflammation)
Pyonephrosis (pye-oh-nef-ROH-sis) or nephropyosis
the suppuration of the kidney (py/o means pus, nephr means kidney, and -osis means abnormal condition or disease); often associated with hydronephrosis