The digestive system

The stages of digestion

Home TeachersDigestive systemThe stages of digestionThe large intestine

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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The large intestine

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THE HARDENING OF STOOLS

The liquid discharged from the small intestine contains a lot of water. Most of this water is absorbed in the large intestine, which is also called the colon.

The colon compresses waste from the digestive process to form faecal matter, also known as stools.

Some types of complex carbohydrates cannot be digested or absorbed by the body, which means they arrive in the colon still intact. You may have heard of these complex carbohydrates; they are called dietary fibre.

The large intestine contains a tremendous amount of bacteria. These bacteria ferment a large part of the dietary fibre. Fermentation makes it easier for stools to pass through, preventing constipation.

ELIMINATION OF STOOLS

Stools contain residues that the body’s cells cannot use or absorb. These are directed towards the anus to be expelled from the body.

In DIGESTIX, any non-absorbed nutrients are rejected once they reach the end of the journey. Everything happens fairly quickly in this game, but in reality, digestion takes much longer.

An average of 15 to 30 hours pass between when food is eaten and when residues are excreted in stools. Even then, only 20% of the residues are eliminated during this time. Because of all the breaking and mixing that occurs during each step of digestion, it actually takes 3 to 7 days for 95% of the residues to be eliminated.

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