upper gastrointestinal tract

The gastrointestinal tract (GI tract), also called the digestive tract, or the alimentary canal, is the system of organs within multicellular animals that takes in food, digests it to extract energy and nutrients, and expels the remaining waste. The major functions of the GI tract are ingestion, digestion, absorption, and excretion.
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Gastrointestinal tract n. The part of the digestive system consisting of the stomach, small intestine, and large intestine. [more]Upper gastrointestinal tract - Community and Resources