The anatomy of the digestive tract
The digestive tract is the name for all the organs that play a part in digestion.
What role does the mouth play in digestion?
Teeth and saliva play an active part in digestion. Teeth cut, tear and crush food while saliva contains enzymes, which break down starch. The food then moves into a tube called the oesophagus, which is about 25 centimetres long.
What are sphincters?
Sphincters help regulate the movement of food from one organ to another. There is a sphincter at the end of the oesophagus to control the entrance to the stomach.
What is the stomach?
The stomach is a large, J-shaped pouch that expands when it receives food and drinks. On average, a stomach can hold 1.3 litres. Did you know that a heavy beer drinker’s stomach could expand to a volume of 4 litres?
What is the small intestine?
The small intestine is a coiled tube that is over 5 metres long. Stretched out, that would be equivalent to the height of a giraffe. The duodenum is the first part of the small intestine.
What is the large intestine?
The large intestine, also called the colon, is the last organ of the digestive tract. It is about 1 metre long. 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.