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The Digestive System

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This is what the human digestive system looks like:



You only need to learn these bits: oesophagus, stomach, small intestine, large intestine, rectum; as well as the glands associated with the digestive system: the salivary glands and the pancreas.


Put simply, the definition of digestion is:


Digestion is the process in which large molecules are hydrolised by enzymes to produce smaller molecules that can be absorbed and assimilated.

It starts in the mouth where food is moistened by saliva and broken down into small parts by chewing. The resulting “bolus” of food is swallowed and travels down the oesophagus and into the stomach, where stomach acid breaks the food down further by breaking the chemical bonds in it. By the time it’s reached the small intestine, food particles are small enough to be absorbed. The leftovers pass down into the large intestine, and then leave the system by a process well known as pooping.

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