Digestive system. Artwork of the digestive system in a man. Digestion is the process where food is converted into a soluble form so that it can be absorbed. In the mouth (top) food is chewed and coated in saliva. The food is swallowed and passes down the oesophagus into the stomach (centre right, orange) where enzymes act. Food moves into the small intestine (coiled, lower centre) where it is further digested by enzymes prior to absorp- tion. The large intestine (bowel, yellow) absorbs water and minerals, converting undigested food to faeces. At centre left is the liver (brown) which regulates nutrients absorbed into the blood; the small gall bladder (green) can also be seen.