How does digestion work?

Digestion is the process of breaking down the big molecules of food that we eat, into smaller molecules that the body can absorb and use. To help break down the food, we need enzymes, which the body produces in various places. Each different type of food group, requires a different type of enzyme. It is important to know which enzyme breaks which food down and where these enzymes are produced. We can talk through it using this diagram and fill in this table as we go. Food first enters at the mouth. Here the salivary glands produce amylase. Amylase breaks down carbohydrates into sugar (glucose). Then food enters the stomach, here protease is the enzyme that works to break down proteins into amino acids. Protease needs an acidic environment to work, hence it works in the stomach. Next, the food travels to the small intestine. The small intestine produces amylase and protease, which we have already met but also produces lipase. Lipase breaks downs fats into fatty acids and glycerol. Amylase, protease and lipase are the 3 enzymes you need to know. All 3 of these enzymes are produces by the pancreas, and they travel into the small intestine too. Whatever is left of the food, after the body has absorbed all the useful bits, travels on into the large intestine and eventually exits the body as faeces.

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Answered by Surina T. Biology tutor

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