Term | Definition |
arteriole | small artery |
bowman capsule | enclosing structure surrounding each glomerulus |
calyx (calix) | cup-like collecting region of the renal pelvis |
catheter | tube for injecting or removing fluids |
cortex | outer region |
creatinine | waste product of muscle metabolism; nitrogenous waste excreted in the urine. |
electrolyte | a chemical element that carries an electrical charge when dissolved in water. essential to cellular function and transmission of impulses in nerve and muscle fibers |
erythropoietin (EPO) | a hormone secreted by the kidney to stimulate the production of red blood cells by bone marrow |
filtration | passive process whereby some substances, but not all, pass through a filter or other material. in the kidney, blood pressure forces materials through the filter (glomerulus) |
glomerulus | tiny ball of capillaries in cortex of the kidney |
hilum | depression or hollow in the part of an organ where blood vessels and nerves enter and leave |
kidney | one of two bean-shaped organs behind the abdominal cavity on either side of the backbone in the lumbar region |
meatus | opening or canal |
medulla | inner region |
micturition | urination; the act of voiding |
nephron | combination of glomerulus and renal tubule where filtration, reabsorption, and secretion take place in the kidney. it is the functional unit of the kidney, each capable of forming urine by itself. |
nitrogenous waste | substance containing nitrogen and excreted in urine |
potassium (K+) | an electrolyte important to body processes. the kidney regulates the concentration within the blood |
reabsorption | in this process, the renal tubules return materials necessary to the body back into the bloodstream |
renal artery | blood vessel that carries blood to the kidney |
renal pelvis | central collecting region in the kidney |
renal tubule | microscopic tube in the kidney in which urine is formed after filtration. in the renal tubule, the composition of urine is altered by the processes of reabsorption and secretion |
renal vein | blood vessel that carries blood away from the kidney and toward the heart |
renin | an enzymatic hormone synthesized, stored, and secreted by the kidney; it raises blood pressure by influencing vasoconstriction |
sodium | an electrolyte regulated in the blood and urine by the kidneys |
trigone | triangular area in the urinary bladder in which the ureters enter and the urethra exits |
urea | major nitrogenous waste product excreted in the urine |
ureter | tube leading from each kidney to the urinary bladder |
urethra | tube leading from the urinary bladder to the outside of the body |
uric acid | a nitrogenous waste excreted in the urine |
urinary bladder | hollow muscular sac that holds and stores urine |
urination | process of expelling urine; also called micturition |
voiding | emptying of urine from the urinary bladder; urination |
glomerulonephritis | inflammation of the kidney glomerulus |
interstitial nephritis | inflammation of the renal interstitium (connective tissue that lies between the renal tubules) |
nephrolithiasis | kidney stones |
nephrotic syndrome | a group of clinical signs and symptoms caused by excessive protein loss in the urine |
polycystic kidney disease (PKD) | multiple fluid-filled sacs (cysts) within and of the kidney |
pyelonephritis | inflammation if the renal pelvis and renal medulla |
renal cell sarcoma (hypernephroma) | cancerous tumor of the kidney in adulthood |
renal failure | failure of the kidney to excrete wastes and maintain its filtration function |
renal hypertension | high blood pressure resulting from kidney disease |
Wilms tumor | malignant tumor of the kidney occurring in childhood |
bladder cancer | malignant tumor of the urinary bladder |
diabetes insipidus | inadequate secretion or resistance of the kidney to the action of antidiuretic hormone |
diabetes mellitus | inadequate secretion or improper utilization of insulin |
blood urea nitrogen (BUN) | measurement of urea levels in blood |
creatinine clearance | measures the rate at which creatinine is cleared from the blood by the kidney |
CT scan | X-ray image showing a detailed cross-sectional view of organs and tissues |
kidneys, uterus, and bladder (KUB) | X-ray examination (without contrast) of the kidneys, uterus, and bladder |
renal angiography | X-ray examination (with contrast) of the vascular system (blood vessels) of the kidney |
retrograde pyelogram (RP) | X-ray imaging of the kidneys, uterus, and bladder after injection of contrast through a urinary catheter into the uterus |
voiding cystourethrogram (VCUG) | X-ray record (with contrast) of the urinary bladder and urethra obtained while the patient is voiding urine |
ultrasonography | process of imaging urinary tract structures using high-frequency sound waves |
radioisotope scan | image of the kidney after injecting into the blood stream a radioactive substance that concentrates in the kidney |
magnetic resonance (MR) | a magnetic field and radio waves produce images of the kidney and surrounding structures in all three planes of the body |
cystoscopy | direct visual examination of the urinary bladder with an endoscope (cystoscope) |
dialysis | process of separating nitrogenous waste materials from the bloodstream when the kidneys no longer function |
lithotripsy | urinary tract stones are crushed and either removed or pass from the body in urine |
renal angioplasty | dilation of narrowed areas in renal arteries |
renal biopsy | removal of kidney tissue for microscopic examination |
renal transplantation | surgical transfer of a kidney from a donor to a recipient |
urinary catheterization | passage of a flexible, tubular instrument through the urethra into the urinary bladder |