Experiments digestion

How can it be that food goes into the body but faeces come out?
The third-grade students got to the bottom of this question in a series of experiments. As little explorers, they studied the path of their own chyme (a chewed slice of bread) through the body. The functions of the individual digestive organs could be experienced both haptically and visually: pantyhose served as the oesophagus through which the chyme was pushed.Vinegar essence served as the stomach acid and the large intestine was embodied by a muslin cloth through which the chyme was pressed in order to add the liquid to the chyme bolus. The little researchers find out that digestion is an exciting and not so disgusting thing as initially thought.
What was probably most interesting for most children was that there is a digestive organ in their bodies that is almost as long as their own classroom. Which digestive organ is that?
Solution (read backwards): enitsetniegral
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