The digestive system, organ by organ
Biology · Key Stage 2 · The School
A long journey
Food does not just disappear once you swallow it. It travels through a long path inside your body. This path is the DIGESTIVE SYSTEM. Several organs sit along this path. Each one does its own job. They work one after another, in order. The whole journey can take more than a day from start to finish. You do not notice most of it happening.
Mouth, oesophagus and stomach
Digestion starts in the MOUTH. Teeth break the food up. Saliva starts to soften it too. Food then slides down a tube called the OESOPHAGUS. It lands in the STOMACH. There, strong muscles churn it about. Acid begins to break it down further. Food can spend several hours in the stomach alone.
Small and large intestine
From the stomach, food moves into the SMALL INTESTINE. Most of the useful nutrients pass into your blood here. What is left then moves into the LARGE INTESTINE. Extra water gets removed there. Only then does waste finally leave the body. The small intestine is actually much longer than the large one, despite its name.
You take a bite of bread. In your MOUTH, teeth and saliva start to break it down. It slides down the OESOPHAGUS to your STOMACH. There, it churns with acid for a while. Next it moves into the SMALL INTESTINE. Nutrients from the bread pass into your blood there. What remains travels into the LARGE INTESTINE. Water gets taken back out. One mouthful. Five organs. Each one doing a different job, on the very same journey.