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Biology - Absorption from the large intestine

Absorption from the large intestine

In humans the material entering the caecum [1] has a high water content.
It also contains substances that cannot be chemically digested. As the
material slowly moves along the large intestine by peristalsis, [2] the
majority of water is absorbed out of the material into the wall of the
intestine to the blood supply.

If the water was not absorbed in the large intestine a large amount of
water would be lost in the faeces. [3] This could result in the person
becoming dehydrated.

Within the colon [4] of humans are bacteria that synthesise (form)
vitamins. For example, _Escherichia coli (E. coli). _synthesises Vitamin K.
The vitamins, along with water, and are absorbed across the walls of the
large intestine.

Material remains in the colons for 12 - 24 hours before it moves into the
last part of the large intestine, the Faeces are normally only stored
briefly in the rectum [5] before they are removed from the body via the



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[3] http://alison.com/#
[4] http://alison.com/#
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