| A | B |
| excretion | process by which wastes and excess substances are removed from an organism |
| metabolic wastes | carbon dioxide, water, nitrogen compounds, mineral salts |
| nitrogen compounds | formed from the breakdown of amino acids |
| elimination | undigested food is passed out of the digestive tract |
| ammonia | chief nitrogenous waste of microorganisms and aquatic animals |
| contractile vacuole | used by some protists to eject water from the cell |
| nephridia | special excretory organs of an earthworm |
| nephridiopore | external opening of an earthworm in which the bladder drains |
| urine | dilute solution of water, mineral salts, ammonia and urea |
| urea | ammonia and carbon dioxide, less poisionous, soluable in water |
| Malpigian tubules | excretory organ of insects |
| uric acid | dry nitrogenous waste passed with feces |
| liver | purifies and detoxifies the blood |
| cirrhosis | excess tissue of the liver cuts blood flow |
| jaundice | too much bile absorbed causing yellow skin |
| kidneys | produce urine from filtered blood |
| ureters | connect kidneys to bladder |
| bladder | holds urine until excreted |
| urethra | carries urine outside the body |
| filtrate | the filtered substance in kidneys |
| cortex | outer part of kidney that filters blood |
| medulla | middle part of kidney made up of collecting ducts |
| collecting ducts | carry filtrate to the pelvis |
| pelvis | inner region of the kidney connect to the ureter |
| nephrons | functional unit of the kidneys that filters waste from blood |
| glomerulus | tight ball of capillaries |
| Bowman's capsule | surrounds the glomerulus |
| dialysis | artificial kidney machine |
| epidermis | dead and dying layers of cells |
| keratin | waterproofing protein |
| dermis | binds skin to muscle and bone; made of connective tissue, glands, blood vessels, nerves, lymph and hair follicles |