Urinary SystemMedical Careers

Ms. Bystrom

Functions

1. Excretion: removing waste from blood

2. Secretion: separation of certain materials from the blood

3. Elimination: emptying urine from the bladder

Organs of the Urinary System

• Kidneys• Ureters• Bladder• Urethra

Kidneys

Two-bean shaped organs located high in the abdominal cavity

External Kidneys

– Covered by a tough fibrous capsule– Hilum: concave border where the renal artery enters and renal vein and ureter exit

Internal Kidney

• Divided into two sections:– Medulla: triangular shaped wedges that separate and remove waste products from blood• Calyces: areas where waste is emptied

– Cortex: smooth areas around medulla

Nephrons• The filtering unit of the kidneys– Over 1 million per kidney– Resembles a funnel with a long, twisted tail

• Function:– filtration: everything in blood is filtered out– Reabsorption: returns useful substances to bloodstream– Secretion: gets rid of waste

The nephron unit

Structures of the Nephron• Bowman’s capsule:– The hard, hollow capsule located ontop of each nephron

• Glomerulus: – cluster of capillaries located inside of eachcapsule

The sections of the Nephron

Ureters

• Long, slender muscular tubes attached to each kidney, leading to the urinary bladder

Ureters

• Peristalsis: wave-like muscular contractions that move urine down the ureter into the bladder

• Calculi: stones that form in the renal pelvis and are washed down the ureter with urine

Urinary bladder• Collapsible bag of muscular tissue that

expands to serve as a reservoir for urine

Urethra• Tube leading from the bladder to the outside

of the body– Sphincters: donut-shaped muscles that permit

voluntary control of bladder function.

Define These Urinary TermsDysuriaPolyuriaOliguriaPyuria

NocturiaHematuria

Urinary Tract Infection (UTI)Define:

•Cystitis•Urethritis•Nephritis

Tests Performed

• Urinalysis: test performed on urine to determine its characteristics

• C & S: culture and sensitivity; test performed to see if bacteria is resistant or sensitive to certain meds

Tests Performed

• Lithotripsy: use of shockwaves to crush stones

• Dialysis: mechanical process of removing waste from blood normally removed by kidneys