Human gastrointestinal tract

The human gastrointestinal tract (GI tract or GIT) is an organ system responsible for transporting and digesting foodstuffs, absorbing nutrients, and expelling waste.

The tract consists of the stomach and intestines, and is divided into the upper and lower gastrointestinal tracts. The GI tract includes all structures between the mouth and the anus, forming a continuous passageway that includes the main organs of digestion, namely, the stomach, small intestine, and large intestine. In contrast, the human digestive system comprises the gastrointestinal tract plus the accessory organs of digestion (the tongue, salivary glands, pancreas, liver, and gallbladder). The tract may also be divided into foregut, midgut, and hindgut, reflecting the embryological origin of each segment.