Urinary System

Main Organs: Kidneys, Ureters, Urinary Bladder, Urethra.

2. Organs of the Urinary System

Kidneys:

Bean-shaped organs located on either side of the spine, just below the rib cage.

Function: Filter blood to produce urine.

Nephron: The microscopic functional unit of the kidney, responsible for filtration, reabsorption, and secretion.

Renal Cortex: Outer region of the kidney.

Renal Medulla: Inner region of the kidney.

Renal Pelvis: Funnel-shaped structure that collects urine from the nephrons and funnels it into the ureter.

Hilum: Indentation on the medial side where blood vessels, nerves, and the ureter enter/exit.

Ureters:

Two muscular tubes that transport urine from the kidneys to the urinary bladder.

Propel urine via peristalsis.

Urinary Bladder:

Hollow, muscular organ that stores urine until it is eliminated from the body.

Micturition (Urination/Voiding): The act of emptying the bladder.

Urethra:

Tube that carries urine from the bladder to the outside of the body.

In males, it also carries semen.

3. Processes of Urine Formation

Glomerular Filtration: Blood is filtered in the glomerulus (part of the nephron), producing filtrate.

Tubular Reabsorption: Useful substances (water, glucose, amino acids, ions) are reabsorbed from the filtrate back into the blood.

Tubular Secretion: Waste products and excess ions are secreted from the blood into the filtrate to be eliminated.

4. Common Medical Terms and Conditions

Anuria: Absence of urine production.

Bacteriuria: Bacteria in the urine.

Cystitis: Inflammation of the urinary bladder.

Dysuria: Painful or difficult urination.

Enuresis: Involuntary discharge of urine (bedwetting).

Glomerulonephritis: Inflammation of the glomeruli in the kidneys.

Hematuria: Blood in the urine.

Hydronephrosis: Swelling of a kidney due to a backup of urine.

Incontinence: Inability to control bladder (or bowel) function.

Nephritis: Inflammation of the kidney.

Nephrolithiasis: Condition of kidney stones.

Nocturia: Frequent urination at night.

Oliguria: Scanty (decreased) urine production.

Polyuria: Excessive urination.

Proteinuria: Presence of protein in the urine.

Pyelonephritis: Inflammation of the kidney and renal pelvis.

Pyuria: Pus in the urine.

Renal Failure: Kidneys lose their ability to remove waste and balance fluids.

Acute Kidney Injury (AKI): Sudden onset.

Chronic Kidney Disease (CKD) / End-Stage Renal Disease (ESRD): Gradual, irreversible loss of function.

Uremia: Accumulation of waste products in the blood due to kidney failure.

Urethritis: Inflammation of the urethra.

Urinary Tract Infection (UTI): Infection in any part of the urinary system.

5. Common Procedures and Tests

Catheterization: Insertion of a tube into the bladder to drain urine.

Cystoscopy: Visual examination of the urinary bladder using a cystoscope.

Dialysis: Artificial filtering of blood when kidneys fail (e.g., Hemodialysis, Peritoneal Dialysis).

Intravenous Pyelogram (IVP): X-ray of the kidneys, ureters, and bladder using contrast dye.