The digestive tract is the name for all the organs involved in digestion.
What role does the mouth play in digestion?Food starts to be transformed in the mouth. Teeth and saliva play an active part in digestion. Teeth cut, tear and crush food while saliva contains enzymes that break down starch. The food then moves into the oesophagus, a tube approximately 25 centimetres long.
What are sphincters?Sphincters are small muscles that help regulate the movement of food from one organ to another. The digestive tract has several sphincters. The sphincter at the end of the oesophagus controls the entrance to the stomach.
What is the stomach?The stomach is a J-shaped muscular pouch that expands when it receives food and drinks. The stomach has an average capacity of 1.3 litres. However, a heavy beer drinker’s stomach could hold a volume of 4 litres!
The
pylorus is the sphincter that controls the movement of food from the stomach to the small intestine.
What is the small intestine?The small intestine is a narrow, coiled tube over 5 metres long. That is equivalent to the height of a giraffe. The
duodenum is the first part of the small intestine. It is closely related to the liver and the pancreas, which are accessory digestive glands.
What is the large intestine?The large intestine, or colon, is the last organ of the digestive tract. It is about 1 metre long.
It is divided into three parts: the ascending colon, the transverse colon and the descending colon.
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Nutrients pass into the
cecum, at the junction of the small intestine and the large intestine, then move all along the colon, which ends with the
anus. A sphincter controls the evacuation of stools through this opening.