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Our sense of smell triggers the production of saliva in our mouths.

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This helps the teeth to crush food as we chew it and is the first step in the process of digestion.

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The tongue shapes the food into a ball called a bolus.

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When we swallow, the bolus passes into the esophagus, which is a stretchy tube that links the back of the throat with the stomach.

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Just wait.

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There's a special flat part at the back of the tongue called the epiglottis,

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which prevents food from going down the windpipe and into the lungs.

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The muscles in the wall of the esophagus slowly squeeze the food down to the stomach.

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The role of the stomach is to break down food.

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It does this by using strong muscular walls

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and excreting gastric juices which mix with the bolus

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and kill dangerous bacteria.

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Once the food is dissolved into a liquid, it passes into the small intestine.

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Here, it mixes with bile produced by the liver

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and pancreatic juices produced by the pancreas.

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The food mixture is broken down into protein, carbohydrates, vitamins, minerals, and fats.

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These nutrients pass through the walls of the small intestine

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and are absorbed into the blood.

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The waste that our body does not need passes to the large intestine.

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Here, water from this waste is absorbed into the blood.

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The solid waste leaves our body through the anus.