Glossary of Terms for
Excretion

Ammonia - the most toxic of the nitrogenous wastes

Bowman's Capsule - a double walled cup shaped structure that surrounds the outside of the glomerulus producing an area of high blood pressure to aid in filtration

Collecting ducts - tubes that carry urine inside the medulla

Cortex - the outside part of the kidney where blood is filtered

Dermis - the layer of skin below the epidermis and is made of elastic connective tissue

Detoxification - the removal of harmful substances from the blood by the liver and converting them to less toxic forms

Epidermis - the outer layer of the skin and is made of tightly bonded epithelial cells

Excretion - Process in which metabolic wastes  are removed from an organism

Feces - solidified undigested and indigestible food which is eliminated by defecation

Filtrate - the solution filtered substances made in Bowman's capsule

Glomerulus - a group of tightly bound capillaries inside the nephron of the kidney

Loop of Henle - the middle section of the renal tube which extends to the medulla; location of reabsorption

Keratin - a tough, water-proof protein produced by cells in the epidermis before they die

Kidneys - a major organ of the urinary system which is responsible for filtering the blood

Malpighian Tubules - excretory organ found in the grasshopper

Medulla - the middle part of the kidney made up of collecting ducts

Nephridia - excretory organ found in the earthworm

Nephrons - part of the kidney where blood is filtered

Pelvis - the inside part of the kidney, that has a cavity connected to the ureter; urine is emptied here by the collecting ducts

Renal Arteries - vessels that bring blood to the kidneys from the descending aorta

Renal Veins - vessels that carry blood out of the kidneys into the inferior vena cava

Sebaceous glands - glands in the skin that produce oily secretions to protect the skin and hair

Sweat glands - glands made of a coiled tube that opens up to the skin's surface and secretes perspiration

Urea - ammonia, the most toxic nitrogenous waste, is converted to urea by the liver

Ureter - a tube that runs from each kidney to the urinary bladder

Urethra - a tube that carries urine from the urinary bladder to outside of the body

Uric Acid- insects, reptiles, and birds excrete a nitrogenous waste product that is dry; the least toxic of the three nitrogenous wastes

Urinary Bladder - a muscular sac that stores the urine until it is excreted

Urinary System - a system made up of the kidneys, bladder, and associated tubes that produces and excretes urine

Urine - dilute fluid containing metabolic wastes which is passed out of the body