The Urinary System

These flashcards cover key vocabulary terms related to the urinary system, including definitions and significant processes.

Urinary System

The organ system that filters nitrogenous wastes from the blood and helps regulate water, electrolyte, and acid-base balances.

Nephron

The structural and functional unit of the kidney, responsible for urine formation.

Glomerulus

A knot of capillaries within the renal corpuscle that forms filtrate through the process of filtration.

Filtrate

Fluid that enters the renal tubule from the glomerulus, essentially blood plasma without proteins.

Tubular reabsorption

The process of reclaiming water, glucose, amino acids, and ions from the filtrate back into the blood.

Tubular secretion

The process of moving substances (such as H+, K+, creatinine) from the blood into the filtrate.

Urea

A nitrogenous waste product formed from protein metabolism, excreted in urine.

Renal pelvis

A funnel-shaped tube that collects urine from the renal calyces and transports it to the ureter.

Micturition

The act of emptying the bladder, involving the contraction of the bladder and relaxation of the sphincters.

Homeostasis

The maintenance of a stable internal environment in the body, crucial for bodily functions.

Renal artery

The artery that supplies blood to the kidneys.

Cortex

The outer region of the kidney, light in color, containing nephron structures.

Medulla

The inner region of the kidney, darker in color, containing renal pyramids.

Arteriole

A small artery that leads to capillaries; afferent arterioles supply blood to the glomeruli.

Ureters

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

Urinary bladder

A muscular sac that stores urine temporarily before elimination from the body.

Urethra

The tube that carries urine from the bladder to the outside of the body.

Antidiuretic hormone (ADH)

A hormone that regulates water balance by controlling water reabsorption in the kidneys.

Aldosterone

A hormone that regulates sodium and potassium balance in the blood.

Acid-base balance

The maintenance of stable pH levels in the body's fluids, primarily regulated by the kidneys.

Diuresis

Increased urine output.

Anuria

An abnormally low urinary output, defined as less than 100 ml/day.

Oliguria

A decreased urinary output between 100 and 400 ml/day.

Ptosis

A condition where kidneys drop to a lower position due to loss of surrounding fat.

Hydronephrosis

A condition characterized by urine backup in the kidneys due to blockage of the ureters.

Cystitis

Inflammation of the bladder, often caused by urinary tract infections.

Pyelonephritis

Inflammation of the kidney, often due to bacterial infection.