Excretory System Vocabulary

Flashcards for vocabulary review on the excretory system.

Excretion

The process of separating wastes from body fluids and eliminating them from the body.

Excretory system

The system that regulates the volume and composition of body fluids by excreting metabolic wastes and recycling some substances for reuse; also known as the urinary system.

Urine

In the kidneys, filtrate of the nephron upon leaving the collecting duct; exits the body through the urethra.

Kidney

One of a pair of organs that filters waste from the blood and adjusts the concentrations of salts in the blood.

Ureter

A pair of muscular tubes that carry urine from the kidneys to the bladder.

Urinary bladder

Organ where urine is stored before being discharged by way of the urethra.

Urethra

The tube through which urine exits the bladder and the body.

Renal artery

Blood vessel that delivers blood to the kidneys.

Renal vein

Blood vessel that drains from the kidney.

Nephron

Microscopic tube-like filtration unit found in the kidneys that filters and reabsorbs various substances from the blood; produces urine.

Bowman’s capsule

In the kidney, the cap-like formation at the top of each nephron that serves as a filtration structure; surrounds the glomerulus.

Glomerulus

In the kidney, a fine network of capillaries within the Bowman’s capsule of the nephron; the walls of the glomerulus act as a filtration device.

Filtrate

In the kidney, filtered fluid that proceeds from the glomerulus into the Bowman’s capsule of the nephron.

Collecting duct

In the kidney, the large pipe-like channel arising from the tubule connected to the Bowman’s capsule in the nephron; functions as a water-conservation device, reabsorbing water from the filtrate in the nephron.

Glomerular filtration

In the kidney, process that results in the movement of water and solutes, except proteins, from the blood plasma into the nephron down a pressure gradient.

Tubular reabsorption

In the kidney, process in which water and useful solutes are reabsorbed from the filtrate in the nephron and transported into capillaries for reuse by the body.

Tubular secretion

In the kidney, process that moves additional wastes and excess substances from the blood into the filtrate in the nephron; uses mainly active transport.

Water reabsorption

In the kidney, process that removes water from the filtrate in the nephron and returns it to the blood for reuse by body systems.

Proximal tubule

In the kidney, tubular portion of the nephron that lies between the Bowman’s capsule and the loop of Henle; main function is reabsorption of water and solutes, as well as secretion of hydrogen ions.

Loop of Henle

In the kidney, tubular portion of the nephron that lies between the proximal tubule and the distal tubule; main function is reabsorption of water and ions.

Distal tubule

In the kidney, tubular portion of the nephron that lies between the loop of Henle and the collecting duct; main function is reabsorption of water and solutes, and secretion of various substances.

Antidiuretic hormone (ADH)

Hormone regulated by the hypothalamus and released by the pituitary gland that increases the permeability of the distal tubule and the collecting duct in the nephrons of the kidneys, allowing more water to be reabsorbed into the blood from the filtrate.

Renal insufficiency

The state in which the kidneys cannot maintain homeostasis due to nephron damage.

Dialysis

Procedure that removes wastes and excess fluid from the blood when kidney function is lost due to renal failure.

Hemodialysis

Type of renal (kidney) dialysis that utilizes an artificial membrane in an external device and is connected to an artery and a vein in a person’s arm to remove waste and excess fluid from the blood when kidney function is lost due to renal failure.

Peritoneal dialysis

Type of renal (kidney) dialysis that utilizes the lining of the intestines, called the peritoneum, as the dialysis membrane to remove waste and excess fluid from the blood when kidney function is lost due to renal failure.