Crash Course : Urinary System part 1

Kidneys

Paired organs that filter blood to remove wastes and regulate homeostasis; contain nephrons

Ureters

Tubes that transport urine from the kidneys to the urinary bladder via peristalsis.

Urinary Bladder

Hollow, muscular organ that temporarily stores urine.

Urethra

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

Nephron

The microscopic functional unit of the kidney where urine formation occurs.

Renal Corpuscle

The blood-filtering component of a nephron, consisting of the glomerulus and Bowman's capsule.

Glomerulus

A ball of high-pressure capillaries in the renal corpuscle where filtration occurs.

Bowman's Capsule

The cup-shaped end of a nephron that surrounds the glomerulus and collects the filtrate.

Renal Tubule

The long, winding tube of a nephron (PCT, Loop of Henle, DCT) where filtrate is processed into urine.

Glomerular Filtration

First step in urine formation; non-selective movement of water/solutes from blood into Bowman's capsule.

Tubular Reabsorption

Process of moving useful substances (water, glucose, ions) from the filtrate back into the blood.

Tubular Secretion

Process of moving specific substances (wastes, drugs, ions) from the blood into the filtrate.

Proximal Convoluted Tubule (PCT)

First part of the renal tubule; site of most reabsorption and some secretion.

Loop of Henle

Hairpin-loop section of the renal tubule crucial for establishing a concentration gradient to conserve water.

Distal Convoluted Tubule (DCT)

Final segment of the renal tubule; site of fine-tuning secretion and reabsorption, often under hormonal control.

Filtrate

The raw fluid produced by glomerular filtration; gets processed into urine.

Homeostasis

The maintenance of a stable internal environment; a key function of the kidneys (e.g., regulating blood volume, pH, ion levels).

Erythropoietin (EPO)

A hormone produced by the kidneys that stimulates red blood cell production in bone marrow.