The large intestine absorbs water and compresses the waste material from digestion to make faecal matter (stools). 

There are complex carbohydrates which cannot be digested and absorbed by the body. These are called dietary fibre. This fibre passes intact into the large intestine.

The large intestine contains many different bacteria. Some dietary fibre can ferment when affected by these intestinal bacteria. This fermentation helps stools pass more easily and prevents constipation.

The stools move through towards the anus, to be expelled outside the body.
 

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