Urinary System (Ch. 7) Chapter Goals Name essential organs of the urinary system and describe their locations and functions. Identify common pathological conditions. Recognize how urinalysis is used and interpreted as a diagnostic test. Define urinary-system-related combining forms, prefixes, and suffixes. List and explain clinical procedures, laboratory tests, and abbreviations that pertain to the urinary system. Understand medical terms in their proper contexts, such as medical reports and records.

Introduction Functions of the kidney Filter nitrogenous wastes to form urine; about 200 quarts of blood are filtered every day to form 2 quarts of urine Maintain proper balance of water, electrolytes (sodium, potassium), and acids Release hormones: Renin: enzymatic hormone important in adjusting blood pressure Erythropoietin (EPO): hormone that stimulates red blood cell production in the bone marrow Calciferol: active form of vitamin D necessary for the absorption of calcium from the intestine Degrade and eliminate hormones from the bloodstream The kidneys also adjust the amount of water and electrolytes for proper muscle and nerve function. Are there other important functions performed by the kidneys?

Anatomy of the Major Organs Organs of the urinary system in a male * What is the size and weight of a normal kidney? Size of fist (4-6 oz) What function is performed by the ureters? Carry urine (paristaltic waves) from kidney to bladder What function is performed by the urinary bladder? Holding tank (reservoir) for urine What function is performed by the urethra? Carries urine from bladder to outside of body

Anatomy of the Major Organs Female urinary system How does the female urinary system differ from the male urinary system? What is the trigone? What function does it perform? (triangle region at base of bladder where ureters enter and the urethra exits. What is micturition? Aka called voiding (process of expelling urine

How Kidneys Produce Urine Blood enters the kidneys through the right and left renal arteries Arterioles carry blood to the capillaries Glomeruli filter the blood The renal artery branches into smaller arteries, arterioles, and glomeruli located throughout the cortex of the kidneys. What is a glomerulus? Each arteriole in cortex of kidney leads to coiled smaller blood vessels called a glomerulus. (tiny capillaries formed into the shape of the ball.) There are approximately one million glomeruli in the cortex of each kidney. How does the kidney regulate blood pressure? Why is maintenance of proper blood pressure important to the kidneys’ function?

Video Clip of the Urinary System

How Kidneys Produce Urine Glomerulus and glomerular/Bowman capsule Blood passes through the glomeruli Glomerular (Bowman) capsule surrounds each glomerulus Renal tubule is attached to each Bowman capsule What functions do the glomerulus, Bowman capsule, and renal tubule perform in the production of urine? Why don’t proteins and blood cells usually appear in the urine? What is the process of reabsorption? What is secretion? What substances make up urine? (Note: These substances become toxic if allowed to accumulate.)

How Kidneys Produce Urine Three steps in the formation of urine Glomerular filtration Tubular reabsorption Tubular secretion What functions are performed in each of the three steps in the formation of urine? The combination of a glomerulus and a renal tubule is called a nephron. There are more than one million nephrons in a kidney.

How Kidneys Produce Urine The glomerulus and a renal tubule combine to form a unit called a nephron.

How Kidneys Produce Urine All collecting tubules lead to the renal pelvis Calyces or calices are small, cuplike regions of the renal pelvis; the term comes from the Greek, kalux, meaning a cup or case surrounding a flower bud Illustration shows section of kidney Notice how secretion and reabsorption are functions of the same organs. Cup-like regions in the renal pelvis are called calyces or calices. Where do all connecting tubules lead? The renal pelvis narrows to form the ureter. To which organ does the ureter lead?

How Kidneys Produce Urine Process of forming and expelling urine How is urine flow from the bladder to the urethra controlled? What triggers the need to urinate? Urine finally exits the body through the urinary meatus.

Terminology: Structures, Substances, and Urinary Symptoms STRUCTURES cyst/o cystitis inflammation of the urinary bladder Combining Form Terminology Meaning Bacterial infections often cause acute or chronic cystitis. In acute cystitis, the bladder contains blood as a result of mucosal hemorrhage (see figure, Acute cystitis). Using the given combining forms, can you form and define other terms not listed in the slide?

Terminology: Structures, Substances, and Urinary Symptoms nephr/o hydronephrosis Condition of excess fluid (water) in the kidney Combining Form Terminology Meaning Obstruction of urine flow may be caused by renal calculi (stones) as shown in the figure. Notice the buildup of excess fluid in the kidney.

Pathologic Conditions-Kidney Glomerulonephritis (Inflammation of the glomeruli within the kidney) Interstitial nephritis (Inflammation of the connective tissue that lies between the renal tubules) Nephrolithiasis (Kidney Stones) Nephrotic syndrome (excessive protein in urine) Polycystic kidneys (PKD) (fluid sacs in kidney) Glomerulonephritis is the inflammation of the glomeruli within the kidney due to infection; it can lead to hypertension and renal failure if untreated. What is interstitial nephritis? What procedure might a physician recommend for a patient with nephrolithiasis? Nephrotic syndrome is a collection of symptoms caused by excessive protein loss in urine. Polycystic kidneys are a hereditary condition characterized by a progressive growth of cysts. There are two types of hereditary PKD. One type is usually asymptomatic until middle age and then is marked by maturia, urinary tract infections, and nephrolithiasis. The other type of PKD occurs in infants or children and results in renal failure.

Pathologic Conditions Kidney Polycystic kidney disease (PKD) PKD—The kidneys contain masses of cysts. Typically polycystic kidneys weigh 20 times more than their usual weight. Polycystic kidneys are a hereditary condition characterized by a progressive growth of cysts.

Laboratory Tests and Clinical Procedures Other clinical procedures Dialysis- artificial kidney machine, filters waste from bloodstream, returns dialyzed blood to the patient’s body. Lithotripsy- urinary tract stones are crushed. The extracorporeal method uses shock waves directed toward the stone from the outside of the body (extra=outside, corpor/o= body). Patient recevies sedation or an anesthetic. Stones pass from body in urine after procedure. Abbreviation is ESWL (Extracorporeal Shock Wave Lithotripsy) Cystoscopy allows for visual examination through a hollow metal tube. What is the difference between hemodialysis and peritoneal dialysis? What procedure might be required to remove kidney stones? Describe the process of catheterization.

Laboratory Tests and Clinical Procedures Other clinical procedures Renal angioplasty- Dilation of narrowed areas in renal arteries. Balloon inserted into artery, then inflated to enlarge vessel. Stent inserted to keep vessel open. Used to treat renal hypertension and preserve kidney function. Renal biopsy-Removal of tissue for examination. Performed 2 ways. 1. performed during surgery (open) 2. or through the skin (closed). Patient lies PRONE, receives local anesthesia, and physician inserts needle into kidney. Tissue viewed. Cystoscopy allows for visual examination through a hollow metal tube. What is the difference between hemodialysis and peritoneal dialysis? What procedure might be required to remove kidney stones? Describe the process of catheterization.

Laboratory Tests and Clinical Procedures Other clinical procedures Renal transplantation- surgical transfer of kidney from a donor to a recipient. Urinary catheterization- used for both short and long term drainage of urine (with tube). A “foley catheter” has a balloon on the end to hold it in place and can deliver solutions into the bladder as well as drain it. Cystoscopy allows for visual examination through a hollow metal tube. What is the difference between hemodialysis and peritoneal dialysis? What procedure might be required to remove kidney stones? Describe the process of catheterization.

Laboratory Tests and Clinical Procedures Cytoscopy—direct visual examination of urinary bladder with an endoscope. Can be performed 2 ways; 1. diagnosis and check-ups. 2. take biopsy, remove polyps, or perform laser treatments. How is a cytoscopy performed?

Laboratory Tests and Clinical Procedures Hemodialysis (HD)