| A | B |
| digestive system | a collection of organs that break down food so that it can be used by the body |
| esophagus | a long, straight tube that connects the mouth and throat to the stomach |
| stomach | a muscular, baglike organ of the digestive tract; attached to the lower end of the esophagus |
| small intestine | a muscular tube about 6 m long; the site of most chemical digestion |
| pancreas | an organ between the stomach and the small intestine that produces enzymes for chemical digestion |
| liver | a large, reddish organ that produces bile and stores nutrients |
| gallbladder | a small, baglike organ that stores bile |
| large intestine | a large organ that reabsorbs water from the digestive tract and stores, compacts, and eliminates indigestible material from the body |
| urinary system | a collection of organs that remove waste from the blood |
| kidney | a bean-shaped organ that removes many harmful substances from the blood |
| nephron | a microscopic filter in the kidney that removes a variety of harmful substances from the blood |
| urine | a concentrated mixture of waste materials that forms in the nephrons of the kidney |
| urinary bladder | a baglike organ that stores urine until it can be eliminated through the urethra |
| antidiuretic hormone | signals kidneys to take back water from the nephrons and return it to the bloodstream |
| diuretics | cause the kidneys to make more urine |