| A | B |
|---|
| nutrition | the process of obtaining raw materials from food |
| ingestion | the act of eating food or drinking; the first stage of food processing |
| digestion | mechanical and chemical breakdown of food into molecules small enough for absorption; the second stage of food processing |
| absorption | uptake of small nutrient molecules; the third stage of food processing |
| elimination | passage of undigested material from the digestive tract; the fourth stage of food processing |
| alimentary canal | digestive tube that extends from the mouth to the anus |
| saliva | liquid secreted into the mouth that contains mucus and digestive enzymes that start chemical digestion |
| bolus | chewed clump of food that leaves the mouth and travels through the alimentary canal |
| pharynx | upper portion of the throat; the junction of the alimentary canal and the trachea |
| esophagus | muscle-encased tube of the alimentary canal that transports food from the pharynx to the stomach |
| peristalsis | series of smooth muscle contractions that push food through the alimentary canal |
| stomach | elastic, muscular sac where some chemical and some mechanical digestion takes place |
| chyme | liquid mixture of food and stomach fluids released from the stomach into the small intestine |
| small intestine | long, narrow tube where digestion is completed and most absorption occurs |
| liver | largest organ in the body; performs many functions such as producing bile, storing glucose and glycogen, and transforming ammonia to urea |
| gallbladder | organ that stores bile from the liver and releases it into the small intestine |
| pancreas | gland that makes digestive enzymes and secretes them into the small intestine; makes the hormones insulin and glucagon and secretes them into the blood |
| villus | fingerlike projection of the inner surface of the small intestine that functions in absorbing nutrients |
| large intestine | portion of the alimentary canal from which water is reabsorbed into the body |
| feces | undigested food material and other waste products that exit the body through the anus |
| essential nutrient | raw material that must be ingested because cells cannot make it from other molecules |
| malnutrition | condition caused by a diet lacking in one or more essential nutrients |
| undernutrition | condition caused by a diet deficient in calories |
| obesity | condition of being significantly overweight |
| anorexia | eating disorder brought about by an extreme pursuit of thinness characterized by self-starvation and excessive weight loss |
| bulimia | eating disorder characterized by bingeing and purging |
